
==== Front
Nat Med
Nat Med
Nature Medicine
1078-8956
1546-170X
Nature Publishing Group US New York

37106168
2315
10.1038/s41591-023-02315-6
Article
CanScreen5, a global repository for breast, cervical and colorectal cancer screening programs
http://orcid.org/0000-0003-4559-1599
Zhang Li 1
http://orcid.org/0000-0001-8886-6244
Mosquera Isabel 1
http://orcid.org/0000-0002-1252-1925
Lucas Eric 1
http://orcid.org/0000-0003-4250-092X
Rol Mary Luz 1
Carvalho Andre L. 1
http://orcid.org/0000-0003-0124-4050
Basu Partha basup@iarc.who.int

1
CanScreen5 collaboratorsSadowski Daniel 2
Natasha Bartlett 3
Budd Alison 3
Nessa Ashrafun 4
De Brabander Isabel 5
Haelens Annemie 5
Pringels Sarah 5
Tairo Jonas 6
Hofvind Solveig 7
Burrion J. B. 8
Valerianova Zdravka 9
Tinmouth Jill 10
Law Cindy 10
Ebenuwah Simbi 11
McCurdy Bronwen 12
Janik Beata 13
Pupwe George 14
Groeneveld Linn Fenna 15
Skare Gry Baadstrand 15
Layne Penelope 16
Sarkeala Tytti 17
Chaila Mwate Joseph 18
Kaminski Michal 13
Kinel Beata 13
Lissowska Jolanta 13
Mumukunde Inga 19
Rodrigues Vitor 20
Rodríguez Robinson 21
Sanz Elena Pérez 22
Alberdi Raquel Zubizarreta 23
Ronco Guglielmo 24
Antoljak Nataša 25
Nakić Dinka 25
Plazanin Davor 25
Parun Andrea Šupe 25
Goossens Mat 26
Nowakowski Andrzej 27
de Koning Harry 28
Dams Els 29
Martin Asha 30
Epermane Mara 31
Jankovska Nataļja 31
Antle Scott 32
Fracheboud Jacques 33
Toes-Zoutendijk Esther 33
van Agt Heleen M. E. 33
Budewig Karen 34
Stomper Barbara 34
Anttila Ahti 35
McLeish Sorana 36
Ramssl-Sauer Alexandra 37
Ziniel Georg 37
Kyprianou Theopisti 38
Pavlou Pavlos 38
Kaliva Fofo 39
Tsantidou Maria 39
Zhang Shaokai 40
Xu Huifang 40
Mushtaq Wali 41
Barragán Biviana Paredes 42
Montalvo Alexandra 43
de la Torre Santos Ana Victoria 44
Guertin Marie-Helene 45
Fournier Sarah 45
Duport Nicolas 46
Májek Ondřej 47
Ngo Ondřej 47
Ivanuš Urška 48
Jarm Katja 48
Primic-Zakelj Maja 48
de Miranda Corrêa Flávia 49
Migowski Arn 49
Cancela Marianna 49
Gallardo Patricia 50
Fattore Gisel 50
Puello Adrián 51
Polanco Víctor 51
Elizaga Nieves Ascunce 52
Fabri Valerie 53
Mantellini Paola 54
Zappa Marco 54
Kellen Eliane 55
Lynge Elsebeth 56
Kääb-Sanyal Vanessa 57
Malek Daniela 57
Chami Youssef 58
Ivanauskiene Rugile 59
Bandhoe Nensy 60
Dillenbourg Claire 61
Heckters Karin 61
Scharpantgen Astrid 61
Ruiz Oris Mariela 62
González Geneva Mireya 62
Arenas Elsa 62
Cacacho Eduardo Alberto Palacios 63
Pomata Alicia 64
Navarro Eliza 64
Mencia Milva 64
Ruiz Gisela Abreu 65
Campoverde Ruth 66
Camel Claudia 67
Donis Rocío 67
Sandoval Yolanda Inés 68
García Heidy 68
Roldán Omaira Isabel 68
del Carmen Moreno Teresa 68
Velado Mario Morales 69
Merino Gina 70
Ríos Juvenal A. 70
Marte Sabrina 71
Hernández Reina Oliva 72
Chacón Marina Anea 72
Ruiz Xiomara Isabel 73
del Carmen Hernández Vivas Xiomara 73
González Roger Iván 73
Ruiz Damaris Isabel Medal 73
Ortega Lourdes 74
Orbegozo Andrea Matos 74
Haro Carlos Adolfo Chuquiyauri 74
Dalmas Miriam 75
Unlu Fahriye 76
Abousselham Loubna 77
De Waldt Rose-Marie 78
Buys Charlotte 78
Hanna Yasine 79
Williams Cathi-Ann 79
Ottey Londi-Ann 79
Philbert-Cyr Shana 80
Emmanuel Crissah 80
Jemmott Alexandra 80
de Miranda Nuno Augusto Alberto 81
Kioupi Stala 82
Asnake Takelech Moges 83
Attia Adel A. 84
Tshisimogo Gontse 85
Seema Lame 85
Banda Jonathan Chiwanda 86
Mustapha Feisul Idzwan 87
Mugolo Rosita Paulo 88
de Alice Miguel Juliao Reginaldo 88
Nyangasi Mary 89
Mwenda Valerian 89
Ferreira Sonia Tavares 90
Barbosa Carla 90
Makua Manala 91
Bakare Yacubu Hervé Julius 92
Charles Myanna 93
Charles Leandra 93
Edwards-France Vera 94
Sewtahal Cheshta 95
Kebirungi Bridget 96
Rwabinumi Mugabe Frank 96
Williams Valarie 97
Zachariah Oritta 97
Scott Arlitha 98
Deleveaux Camille 99
Campbell Martin 100
Ferreira Cesaltina 101
Perera Suraj 102
Silva Padmaka 102
Kumarapeli Vindya 102
Grant-Tate Merisa 103
Tulloch Cherie 104
Saika Kumiko 105
Lee Kyeongmin 106
Jun Jae Kwan 106
Mukete Sona Franklin 107
Dimitrov Plamen 108
Momkuviene Vaida 109
Zaksas Viačeslavas 109
Veerus Piret 110
Bric Tatjana Kofol 111
Mlakar Dominika Novak 111
Škrjanec Ana Lucija 111
Zakotnik Jožica Maučec 111
Skhirtladze Tamar 112
Xuereb Stephanie 113
Colquhoun Carol 114
Sangrajrang Suleeporn 115
Eshwar Kumar 116
Stanners Greig 117
Black Roger 117
Andreassen Trude 118
Budai Andras 119
Döbrõssy Lajos 119
Kovács Attila 119
Nicula Florian 120
Portillo Isabel 121
Altzibar Jone Miren 121
Arenaza Edurne 121
Simango Ndabaningi 122
Espinàs Josep A. 123
Glinton-Rolle Constance 124
Anews-Barr Jeanette 124
Capote Mariana 125
Fazzino Marisa 125
Armstrong Claire 126
Gamble Andrew 126
Mc Innes Kenneth 126
Wright Suzanne 127
Clayton Helen 128
Latinovic Radoslav 129
Mackie Anne 129
Rimmer Janet 129
Hall Clare 126
Elfström Klara Miriam 130
Törnberg Sven 130
Zorzi Manuel 131
Leja Marcis 132
Rezeberga Dace 133
Hagenimana Marc 134
Hamers Françoise 135
Rogel Agnès 135
Assogba Frank 135
Fitzpatrick Patricia 136
Arbyn Marc 137
Figueroa Jacqueline 138
Rovelo Alex 138
Salinas Erosloa 138
Argüello Elías Yused 139
Castillo Adriana Milano 139
Rosas Velia 139
Špánik Stanislav 140
Houmann Merete Rønmos 141
Johansen Dorte 142
Dillner Joakim 143
Oswal Kunal 144
Huang Yubei 145
Siala Ismail M. 146
Candeur Michel 147
Hoeck Sarah 148
Borras Josep M. 149
Bleyen Luc 150
Guzha Bothwell Takaingofa 151
Olivier Adie Yao Mesmin 92
Fasching Elisabeth 152
Vienna Alexander Gollmer Gesundheit Österreich 152
Taohid Tonoy 153
Bencomo Walkiria Bermejo 154
Tejada Darbelis 155
Valletta Joseph Psaila 156
Nisbett Judy 157
Baptiste Damaris 158
Layne Melanie Ann 158

1 grid.17703.32 0000000405980095 International Agency for Research on Cancer, Lyon, France
2 Alberta Colorectal Cancer Screening Program, Edmonton, Alberta Canada
3 grid.414104.4 0000 0004 1936 7726 Australian Institute of Health and Welfare, Canberra, Australian Capital Territory Australia
4 grid.411509.8 0000 0001 2034 9320 Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh
5 Belgian Cancer Registry, Brussels, Belgium
6 Benjamin Mkapa Hospital, Dar es Salaam, Dodoma, United Republic of Tanzania
7 Breast Screen Norway, Oslo, Norway
8 Brumammo, Brussels, Belgium
9 Bulgarian National Cancer Registry, Sofia, Bulgaria
10 Canadian Screening for CRC Research Network, Oakville, Ontario Canada
11 grid.419404.c 0000 0001 0701 0170 Cancer Care Manitoba, Winnipeg, Manitoba Canada
12 grid.419887.b 0000 0001 0747 0732 Cancer Care Ontario, Toronto, Ontario Canada
13 grid.418165.f 0000 0004 0540 2543 Cancer Center and Maria Skłodowska-Curie Institute of Oncology, Warsaw, Poland
14 Cancer Diseases Hospital, Lusaka, Zambia
15 grid.418941.1 0000 0001 0727 140X Cancer Registry Norway, Oslo, Norway
16 Cancer Registry, Georgetown, Guyana
17 grid.469387.7 0000 0001 0674 157X Cancer Society of Finland, Helsinki, Finland
18 Catholic Relief Services, Lusaka, Zambia
19 Clinton Health Acces Initiative, Kigali, Rwanda
20 grid.8051.c 0000 0000 9511 4342 Coimbra University/Liga Portuguesa Contrao Cancro, Coimbra, Portugal
21 grid.419065.f 0000 0004 0453 9978 Comision Honoraria de Lucha Contra el Cáncer, Montevideo, Uruguay
22 grid.417564.5 Conselleria de Sanitat Universali Salut Pública–Generalitat Valenciana, Valencia, Spain
23 Conselleria de Sanidade Xuntade Galicia Santiago de Compostela, A Coruña, Spain
24 Centro di Riferimento per l’Epidemiologia e la Prevenzione Oncologica in Piemonte and University Hospital ‘Città della Salute e della Scienza’, Turin, Italy
25 grid.413299.4 0000 0000 8878 5439 Croatian Institute of Public Health, Zagreb, Croatia
26 Centrum voor Kankeropsporing, Bruges, Belgium
27 grid.415641.3 0000 0004 0620 0839 Department of Gynaecology and Oncologic Gynaecology, Military Institute of Medicine, Warsaw, Poland
28 grid.5645.2 000000040459992X Department of Public Health, Erasmus MC, Rotterdam, the Netherlands
29 Diakonessen Hospital, Paramaribo, Suriname
30 Dominica China Friendship Hospital, Roseau, Dominica
31 East Riga Clinical University Hospital, Riga, Latvia
32 Eastern Health, Saint John’s, Newfoundland and Labrador Canada
33 grid.5645.2 000000040459992X Erasmus Medical Centre, Rotterdam, the Netherlands
34 grid.432880.5 0000 0001 2179 9550 Federal Ministry of Health, Bonn, Germany
35 Finnish Cancer Registry/Cancer Society of Finland, Helsinki, Finland
36 General Hospital, Saint George’s, Grenada
37 grid.502403.0 0000 0004 0437 2768 Gesundheit Österreich, Vienna, Austria
38 grid.426504.1 Health Monitoring Unit, Ministry of Health, Nicosia, Cyprus
39 grid.484204.e Hellenic Ministry of Health, Athens, Greece
40 grid.414008.9 0000 0004 1799 4638 Henan Cancer Hospital, Zhengzhou, China
41 Hospital de Especialidades Eugenio Espejo, Quito, Ecuador
42 Hospital Enrique Garcés, Quito, Ecuador
43 Hospital General Pablo Arturo Suárez, Quito, Ecuador
44 Hospital Provincial de Villa Clara, Santa Clara, Cuba
45 grid.434819.3 0000 0000 8929 2775 Institut National de Santé Publique du Quebec, Quebec City, Quebec Canada
46 grid.419184.1 0000 0001 2183 8361 Institut de Veille Sanitaire Saint-Maurice, Saint-Maurice, France
47 grid.486651.8 0000 0001 2231 0366 Institute of Health Information and Statistics of the Czech Republic, Prague, Czech Republic
48 grid.418872.0 0000 0000 8704 8090 Institute of Oncology Ljubljana, Ljubljana, Slovenia
49 grid.419166.d Instituto Nacional de Câncer, Rio de Janeiro, Brazil
50 Instituto Nacional del Cáncer, Buenos Aires, Argentina
51 Instituto Nacional del Cáncer Rosa Emilia Sánchez Pérez de Tavarez, Santo Domingo, Dominican Republic
52 Instituto de Salud Públicay Laboral de Navarra Pamplona, Navarra, Spain
53 grid.490631.9 Intermutualistic Agency, Brussels, Belgium
54 grid.417623.5 0000 0004 1758 0566 Istituto per lo Studio e la Prevenzione Oncologica, Florence, Italy
55 grid.5596.f 0000 0001 0668 7884 Katholieke Universiteit Leuven, Leuven, Belgium
56 grid.5254.6 0000 0001 0674 042X Københavns Universitet Copenhagen, Copenhagen, Denmark
57 Kooperationsgemeinschaft Mammographie, Berlin, Germany
58 Lalla Salma Foundation-Cancer Prevention and Treatment, Rabat, Morocco
59 grid.45083.3a 0000 0004 0432 6841 Lithuanian University of Health Sciences Kaunas, Kaunas, Lithuania
60 Lobi Health Center Foundation, Paramaribo, Suriname
61 grid.494279.5 Ministère de la Santé, Luxembourg, Luxembourg
62 Ministerio de Salud, Panama City, Panama
63 Ministerio de Salud Pública y Asistencia Social, Guatemala City, Guatemala
64 grid.508033.d 0000 0004 0453 6902 Ministerio de Salud Pública y Bienestar Social, Asunción, Paraguay
65 grid.419874.7 0000 0001 0671 2840 Ministerio de Salud Pública, La Habana, Cuba
66 grid.511900.c 0000 0004 1762 5226 Ministerio de Salud Pública, Quito, Ecuador
67 Ministerio de Salud y Asistencia Social, Guatemala City, Guatemala
68 grid.454083.e Ministerio de Salud y Protección Social, Bogotá, Colombia
69 grid.490695.7 0000 0004 0521 0269 Ministerio de Salud, Unidad Nacional para la Prevención y Control del Cáncer San Salvador, San Salvador, El Salvador
70 grid.415779.9 Ministerio de Salud, Metropolitana, Chile
71 Ministerio de Salud, Santo Domingo, Dominican Republic
72 grid.490695.7 0000 0004 0521 0269 Ministerio de Salud, San Salvador, El Salvador
73 grid.419860.2 0000 0004 0466 383X Ministerio de Salud, Managua, Nicaragua
74 grid.419858.9 0000 0004 0371 3700 Ministerio de Salud, Lima, Peru
75 Ministry for Energy and Health, Valletta, Malta
76 grid.415700.7 0000 0004 0643 0095 Ministry of Health, Ankara, Turkey
77 grid.434766.4 0000 0004 0391 3171 Ministry of Health and Social Protection, Rabat, Morocco
78 grid.463501.5 Ministry of Health and Social Services, Windhoek, Namibia
79 grid.415730.4 0000 0004 0368 1307 Ministry of Health and Wellness, Kingston, Jamaica
80 grid.494365.9 Ministry of Health and Wellness, Castries, Saint Lucia
81 grid.420634.7 0000 0001 0807 4731 Ministry of Health, Lisbon, Portugal
82 grid.426504.1 Health Monitoring Unit, Ministry of Health Nicosia, Nicosia, Cyprus
83 grid.414835.f 0000 0004 0439 6364 Ministry of Health, Addis Ababa, Ethiopia
84 Ministry of Health, Benghazi, Libya
85 grid.415807.f Ministry of Health, Gaborone, Botswana
86 grid.415722.7 0000 0004 0598 3405 Ministry of Health, Lilongwe, Malawi
87 grid.415759.b 0000 0001 0690 5255 Ministry of Health, Putrajaya, Malaysia
88 grid.415752.0 0000 0004 0457 1249 Ministry of Health, Maputo, Mozambique
89 grid.415727.2 Ministry of Health, Nairobi, Kenya
90 Ministry of Health, Praia, Republic of Cabo Verde
91 Ministry of Health, Pretoria, South Africa
92 Ministry of Health, Public Hygiene and Universal Health Coverage, Abidjan, Côte d’Ivoire
93 Ministry of Health, Saint George’s, Grenada
94 Health Promotion Unit, Ministry of Health, Basseterre, Saint Kitts and Nevis
95 Ministry of Health, Paramaribo, Suriname
96 grid.415705.2 Ministry of Health, Kampala, Uganda
97 Ministry of Health, Wellness and the Environment, Saint John’s, Antigua and Barbuda
98 Ministry of Health, Kingstown, Saint Vincent and the Grenadines
99 grid.493875.4 Ministry of Health, Nassau, Bahamas
100 Ministry of Health, Georgetown, Guyana
101 grid.415752.0 0000 0004 0457 1249 Ministry of Health, Maputo, Mozambique
102 grid.466905.8 Ministry of Health, Colombo, Sri Lanka
103 Ministry of Health, Basseterre, Saint Kitts and Nevis
104 Mount St. John’s Medical Centre Antigua, Saint John’s, Antigua and Barbuda
105 grid.272242.3 0000 0001 2168 5385 National Cancer Center, Tokyo, Japan
106 grid.410914.9 0000 0004 0628 9810 National Cancer Center, Gyeonggi-do, Republic of Korea
107 National Cancer Control Committee, Yaounde, Cameroon
108 grid.416574.5 National Center of Public Health and Analyses, Sofia, Bulgaria
109 National Health Insurance Fund, Ministry of Health, Vilnius, Lithuania
110 grid.416712.7 0000 0001 0806 1156 National Institute for Health Development, Tallinn, Estonia
111 grid.414776.7 National Institute of Public Health, Ljubljana, Slovenia
112 National Screening Center, Tbilisi, Georgia
113 National Screening Programmes, Ministry for Energy and Health, Valletta, Malta
114 National Specialist and Screening Services Directorate Procurement Commissioning and Facilities, Edinburgh, Scotland
115 grid.419173.9 0000 0000 9607 5779 National Cancer Institute, Bangkok, Thailand
116 New Brunswick Cancer Network, Fredericton, New Brunswick Canada
117 grid.422655.2 0000 0000 9506 6213 NHS National Services Scotland, Edinburgh, Scotland
118 grid.461584.a 0000 0001 0093 1110 Norwegian Directorate of Health, Oslo, Norway
119 grid.452133.2 0000 0004 0636 7321 Office of the Chief Medical Officer, Budapest, Hungary
120 Oncology Institute, Romanian NV Regional Cervical Cancer Screening Programme Management Unit, Cluj-Napoca, Romania
121 grid.426049.d 0000 0004 1793 9479 Osakidetza-Servicio Vasco de Salud, Basque Country, Spain
122 grid.417158.e 0000 0004 0463 0325 Parirenyatwa Hospital, Harare, Zimbabwe
123 Pla Director d’oncologia L’Hospitalet de Llobregat, Llobregat, Spain
124 Princess Margaret Hospital, Nassau, Bahamas
125 Programa Nacional del Cáncer, Montevideo, Uruguay
126 grid.454053.3 0000 0004 0494 5490 Public Health Agency, Quality Assurance Reference Centre, Northern Ireland Cancer Screening Programmes, Belfast, Northern Ireland
127 grid.271308.f 0000 0004 5909 016X Public Health England Screening, London, UK
128 grid.439475.8 0000 0004 6360 002X Public Health Wales, Cardiff, Wales
129 grid.271308.f 0000 0004 5909 016X Public Health England, London, UK
130 Regionalt Cancer Centrum Stockholm-Gotland, Stockholm, Sweden
131 Registro Tumori del Veneto, Venice, Italy
132 grid.488518.8 0000 0004 0375 2558 Riga East University Hospital, University of Latvia, Riga, Latvia
133 grid.17330.36 0000 0001 2173 9398 Riga Stradins University, Riga, Latvia
134 grid.452755.4 0000 0004 0563 1469 Rwanda Biomedical Centre, Kigali, Rwanda
135 grid.493975.5 0000 0004 5948 8741 Santé Publique France Saint-Maurice, Saint-Maurice, France
136 School of Public Health, Physiotherapy and Sports Science and National Screening Service, Dublin, Ireland
137 grid.418170.b 0000 0004 0635 3376 Scientific Institute of Public Health, Brussels, Belgium
138 grid.490705.f 0000 0004 0372 3407 Secretaria de Salud, Tegucigalpa, Honduras
139 grid.415745.6 0000 0004 1791 0836 Secretaría de Salud, Mexico City, Mexico
140 Saint Elisabeth Cancer Institute, Bratislava, Slovak Republic
141 grid.6203.7 0000 0004 0417 4147 Statens Serum Institut, Copenhagen, Denmark
142 Sundhedsdatastyrelsen, Copenhagen, Denmark
143 Swedish Cervical Screening Registry, Stockholm, Sweden
144 grid.468639.6 0000 0004 6445 3762 Tata Trusts (Alamelu Charitable Foundation), Vijayawada, India
145 grid.411918.4 0000 0004 1798 6427 Tianjin Medical University Cancer Institute & Hospital, Tianjin, China
146 Tripoli Cancer Center, Tripoli, Libya
147 grid.4989.c 0000 0001 2348 0746 Université Libre de Bruxelles, Brussels, Belgium
148 grid.5284.b 0000 0001 0790 3681 University of Antwerp, Antwerp, Belgium
149 grid.5841.8 0000 0004 1937 0247 University of Barcelona, Barcelona, Spain
150 grid.5342.0 0000 0001 2069 7798 University of Ghent, Ghent, Belgium
151 grid.13001.33 0000 0004 0572 0760 Faculty of Medicine and Health, University of Zimbabwe, Harare, Zimbabwe
152 Vienna, Austria
153 Dhaka, Bangladesh
154 Havana, Cuba
155 Santo Domingo, Dominican Republic
156 Valletta, Malta
157 Basseterre, Saint Kitts and Nevis
158 Kingstown, Saint Vincent and the Grenadines
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© The Author(s) 2023
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The CanScreen5 project is a global cancer screening data repository that aims to report the status and performance of breast, cervical and colorectal cancer screening programs using a harmonized set of criteria and indicators. Data collected mainly from the Ministry of Health in each country underwent quality validation and ultimately became publicly available through a Web-based portal. Until September 2022, 84 participating countries reported data for breast (n = 57), cervical (n = 75) or colorectal (n = 51) cancer screening programs in the repository. Substantial heterogeneity was observed regarding program organization and performance. Reported screening coverage ranged from 1.7% (Bangladesh) to 85.5% (England, United Kingdom) for breast cancer, from 2.1% (Côte d’Ivoire) to 86.3% (Sweden) for cervical cancer, and from 0.6% (Hungary) to 64.5% (the Netherlands) for colorectal cancer screening programs. Large variability was observed regarding compliance to further assessment of screening programs and detection rates reported for precancers and cancers. A concern is lack of data to estimate performance indicators across the screening continuum. This underscores the need for programs to incorporate quality assurance protocols supported by robust information systems. Program organization requires improvement in resource-limited settings, where screening is likely to be resource-stratified and tailored to country-specific situations.

In the first results from an ongoing global cancer screening data repository, screening program organization was better overall in Europe compared to other continents; however, there were substantial gaps in implementation across both high- and low-resource settings.

Subject terms

Population screening
Health care
issue-copyright-statement© Springer Nature America, Inc. 2023
==== Body
pmcMain

A decline in cancer-specific mortality can be achieved through the implementation of screening programs for specific cancers; such programs need effective planning, adequate financial, human and technical resources, and stringent quality control1. Following the experiences of high-income countries (HICs), several low- and middle-income countries (LMICs) have included cancer screening programs in their national cancer control plans2. Many such screening programs, most being in LMICs and some even in HICs, have failed to deliver the expected clinical benefits3,4. One of the key factors contributing to the ineffective nature of these programs is the absence of an information system to collect performance data across the screening continuum, from the identification of the target population to the treatment and follow-up of screen-detected cancers and precursor lesions, and using the same for quality improvement of the program. An organization collecting individual-level data of the population offered cancer screening using an information system, and using the same for program management is known as a screening registry.

Many European Union (EU) Member States have remained at the forefront of implementing quality-assured, population-based cancer screening programs with a strong political commitment and adequate resource allocation. These programs are guided mostly by evidence-based recommendations from European quality assurance guidelines in breast, cervical and colorectal cancer (CRC) screening, which consistently highlight the necessity of regular monitoring and evaluation5–7. To achieve this, a cancer screening registry is vital to collect, use and store cancer screening data at the individual level that underpins the entire continuum of cancer screening. A screening registry is also an essential tool to implement invitation-based screening and track screen-positive individuals to ensure their compliance to further management.

The International Agency for Research on Cancer (IARC) reported the status and the performance of cancer screening programs from EU Member States in the years 2008 and 2017 (refs. 8,9). Such consecutive evaluations permit comparisons in the performance of screening programs using a harmonized set of indicators. Outside the EU, cancer screening evaluation reports have only been published regularly in a few countries10,11. Most LMICs have only been reporting screening coverage based on population surveys because of logistic, fiscal and organizational challenges of data collection across the screening continuum12,13.

In 2019, IARC launched the Cancer Screening in Five Continents (CanScreen5) project, which aims to collect, analyze and disseminate information on cancer screening programs globally, and encourage and support countries to routinely collect screening performance data. This global project gathers information and performance data on breast, cervical and CRC screening programs in a standardized manner using an online portal (https://canscreen5.iarc.fr/). Validated data made publicly available through the portal will support program managers in cancer screening evaluation, benchmarking, quality improvement and informed policy formulation. This study describes how the CanScreen5 project works and reports the status, organization and performance of screening programs that have participated in the project up to September 2022. The key outcomes of the current study and their implications to inform policies in cancer screening are displayed in Table 1.Table 1 Policy summary and key outcomes

Background	Quality improvement supported by continuous monitoring and evaluation of performance is vital for cancer screening programs. However, there is a lack of global data to evaluate cancer screening implementation in the real world, especially data from LMICs. This prevents such programs from setting their own benchmarks and compare performance with similar regional programs. IARC initiated the CanScreen5 project, a global cancer screening data repository, to fill this gap.	
Main findings and limitations	Eighty-four countries joined the CanScreen5 project and shared qualitative or quantitative (or both) data on breast cancer, cervical cancer and CRC screening programs. Substantial heterogeneity exists between cancer sites and between countries regarding program organization, covering screening policies, protocols, governance, financing mechanisms, systems of invitation and recall, processing of data collected for program monitoring and quality assurance. Overall, organization was better in cancer screening programs from Europe than other continents. For specific cancer sites, CRC screening programs showed better organization. Similarly, considerable heterogeneity existed in program performance as noted through the estimation of harmonized indicators. Examination coverage ranged from 1.7% (Bangladesh) to 85.5% (England, United Kingdom) for breast cancer, from 2.1% (Côte d’Ivoire) to 86.3% (Sweden) for cervical cancer, and from 0.6% (Hungary) to 64.5% (the Netherlands) for CRC screening programs. The proportion advised further assessment following a screening test ranged from 0.6% (Chile) to 14.4% (Republic of Korea) for mammography-based screening and from 1.0% (Mozambique) to 2.8% (Bangladesh) for clinical breast examination-based breast cancer screening programs; from 0.5% (Sri Lanka) to 7.8% for cytology (Uruguay); from 2.3% (Kenya) to 78.8% (Ethiopia) for VIA-based cervical screening programs; and from 2.3% (Calvados, France) to 27.2% (Uruguay) for FIT-based CRC screening programs. Regardless of the screening protocol, further assessment participation rates varied substantially across cancer sites and countries, ranging from 39.7% in Morocco to 100% in the Czech Republic, Denmark and Portugal for breast cancer, from 39.0% in Poland to 100% in Hungary for cervical cancer, and from 33.0% in the Republic of Korea to 97.6% in the Czech Republic for CRC screening programs. The high variability in screening test and protocol, test positivity and further assessment compliance was reflected in the precancer and cancer detection rates.	
Policy implications	Substantial heterogeneity in screening program performance revealed by the first batch of data from the CanScreen5 project underscores the need for many such programs to do further in-depth analysis of their performance, identify the scope for improvement and take appropriate measures. To implement corrective actions, program managers need to be aware of the implications of the outcome indicators; for example, a low detection rate may indicate poor performance of the screening or diagnostic tests (or both) or low compliance of screen-positives, but may also be due to low prevalence of disease especially in a frequently screened population. The gap in data collection across the screening continuum in both high- and low-resource settings is a concern. Programs need to build robust information systems to be able to capture screening performance data and use the same for quality improvement. Almost all countries worldwide have invested greatly to strengthen disease surveillance mechanisms (including improvement of health information systems) to mitigate the COVID disease pandemic. Cancer screening programs need to leverage these new developments to improve their own performance and quality.	

Results

Up to September 2022, a total of 84 countries from 5 continents have participated in the CanScreen5 project, including 17 countries from Africa, 27 from the Americas, 10 from Asia, 29 from Europe and 1 from Oceania (Australia). Among these countries, seven (Antigua and Barbuda, Bulgaria, Dominica, Ecuador, Libya, Saint Kitts and Nevis and Saint Lucia) were not included in the analysis because they did not fulfill the minimum criteria of having a screening program for the cancer sites they submitted information on. Fifty-seven countries reported for breast cancer, 75 for cervical cancer and 51 for CRC screening programs. Most of the countries (88.1%, n = 74) reported for national programs, while others (Canada, China and India) reported only one or more regional programs (Fig. 1a–c).Fig. 1 The status of data collection for the CanScreen5 project from various countries for breast cancer, cervical cancer and CRC screening programs.

a–c, Status of data collection for breast cancer (a), cervical cancer (b) and CRC (c) screening. The dotted and dashed lines on the maps represent approximate borderlines for which there may not be full agreement as yet. The designations used and the presentation of the material in this publication do not imply the expression of any opinion whatsoever on the part of the WHO/IARC concerning the legal status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries. Map disclaimer: all rights reserved.

Breast cancer screening programs

Data were obtained from 57 breast cancer screening programs (including regional ones), 4 from Africa, 16 from the Americas, 9 from Asia, 27 from Europe and 1 from Oceania (Australia). Extended Data Tables 1 and 2 provide a summary of the qualitative information on breast cancer screening programs by continent.

Policies, protocol and organization

Almost half of the European programs (n = 12, 44.4%) have a law mandating the government to provide a national breast cancer screening program; however, there were fewer such programs in the Americas (n = 3, 18.8%) and Asia (n = 2, 22.2%), and none in Africa or Australia. Most programs started in 2000 or later and reported having an individual or a team responsible for implementing the screening activities. While 87.7% of programs provided free-of-charge screening services across the continents (Africa (n = 3, 75.0%), Americas (n = 13, 81.3%), Asia (n = 8, 88.9%), Europe (n = 25, 92.6%) and Australia), fewer (64.9%) provided free-of-charge diagnostic services (Africa (n = 1, 25.0%), Americas (n = 9, 56.3%), Asia (n = 5, 55.6%), Europe (n = 22, 81.5%) and Australia).

Mammography was the screening test in all European programs, in Australia and in the Americas (n = 15, 93.8%); however, only one-third of programs in Asia (n = 3, 33.3%) adopted mammography as the screening test. Double reading of mammograms was widely practiced in Europe and Australia but not in the Americas. Clinical breast examination (CBE) was the primary screening test in all African programs.

Invitation to eligible women to participate in screening was reported by 96.3% (n = 26) of European programs; however, only 12.5% of programs in the Americas and no programs in Africa did so. Active tracking of screening-positive women to ensure their compliance was performed in screening programs from Africa (n = 2, 50%), the Americas (n = 10, 62.5%), Asia (n = 6, 66.7%), Europe (n = 23, 85.2%) and Australia. Most of the programs in Europe (n = 24, 88.9%), Asia (n = 7, 77.8%), the Americas (n = 9, 56.3%) and Australia, but only 1 program in Africa (25%), reported data collection on an individual basis. Likewise, the capability of the programs to link with population-based cancer registries (PBCRs) was highly variable across the continents. Heterogeneity also existed in the manner of quality assurance.

Quantitative performance data

A comparative analysis of quantitative data on performance collected from 42 breast cancer screening programs (including regional ones) is presented in Fig. 2. Details of the data according to each country can be found in Supplementary Table 1. Screening examination coverage was highly heterogeneous, with reported coverage ranging from 1.7% in Bangladesh to 85.5% in England. Considerable heterogeneity was also observed for the proportion of women put forward for further assessment, ranging from 0.6% (Chile) to 14.4% (Republic of Korea) for mammography-based screening and 1.0% (Mozambique) to 2.8% (Bangladesh) for CBE-based protocols. Furthermore, the assessment participation rate exceeded 90% in most European countries (except in Nicosia (Cyprus) and Wallonia (Belgium)) and Japan, while the rate was only 39.7% in Morocco. For programs adopting mammography as the screening method, the detection rate of carcinoma in situ of the breast ranged from 0.1 per 1,000 (Estonia and Poland) to 2.1 per 1,000 (Wales, United Kingdom); the detection rate for invasive cancer ranged from 1.9 per 1,000 (Portugal) to 8.1 per 1,000 (Wales, United Kingdom). Morocco was the only country with a CBE-based program that provided data on invasive cancers detected; the detection rate of invasive cancer was 0.9 per 1,000.Fig. 2 Comparative values of selected performance indicators for the breast cancer screening programs that provided data to the CanScreen5 project.

The reporting format is country or region, reporting year and screening protocol. Mx, mammography. aMexico: the target population is not the total of individuals eligible for screening (age-based). bJapan: women with a negative screening test receiving further assessment due to clinical recommendation were also included.

Analysis according to World Bank income status

We also analyzed the results according to the World Bank income classification of countries (Supplementary Table 5). HICs had better organized screening programs compared to LMICs, which was supported by a law mandating screening provision in 41.2% (n = 14) of them. Compared to LMICs, HICs were also more likely to have an invitation system in place (n = 29, 85.3%) and use mammography as the primary screening test (n = 33, 97.1%), with double reading of all mammograms (n = 23, 67.6%); 85.3% of HICs (n = 29) had an information system that collects individual data.

Cervical cancer screening programs

Seventy-five cervical screening programs (including regional ones) reported data for the CanScreen5 project, 16 from Africa, 22 from the Americas, 9 from Asia, 27 from Europe and 1 from Oceania (Australia). Extended Data Tables 3 and 4 provide a summary of the qualitative information on 75 cervical screening programs by continent.

Policies, protocol and organization

Policies for cervical screening were mandated by law in 16% (n = 12) of the programs (Americas (n = 3, 13.6%), Asia (n = 2, 22.2%), Europe (n = 7, 25.9%)). Screening programs started before 2000 in the Americas (n = 9, 40.9%), Europe (n = 9, 33.3%), Asia (n = 2, 22.2%), Africa (n = 1, 6.3%) and Australia. Cervical screening services were provided free of charge in 88% of the programs in the project (Africa (n = 13, 81.3%), Americas (n = 19, 86.4%), Asia (n = 8, 88.9%), Europe (n = 25, 92.6%) and Australia). However, colposcopy and biopsy were only available as payable services in Africa (n = 8, 50.0%), the Americas (n = 13, 59.1%), Asia (n = 5, 55.6%) and Europe (n = 21, 77.8%). Screening tests were administered free of charge in Australia. Whether women have to pay for diagnostic tests depends on their insurance coverage.

While cytology was the most frequently used screening test in the Americas (n = 21, 95.5%), Asia (n = 6, 66.7%) and Europe (n = 27, 100%), 93.8% (n = 15) of the programs in Africa reported using visual inspection with acetic acid (VIA). Human papillomavirus (HPV)-based screening (with or without cytology) was already introduced in Africa (n = 4, 25.0%), the Americas (n = 10, 45.5%), Asia (n = 2, 22.2%), Europe (n = 9, 33.3%) and Australia.

Screening invitation was reported in Europe (n = 21, 77.8%), Asia (n = 5, 55.6%), the Americas (n = 5, 22.7%) and Australia, but not in Africa. Most countries in Africa (n = 9, 56.3%) only invited human immunodeficiency virus-positive women for cervical screening. Individual-level data collection has been reported in Africa (n = 3; 18.8%), the Americas (n = 14, 63.6%), Asia (n = 7, 77.8%), Europe 74.1% (n = 20, 74.1%) and Australia. A link with PBCR was present in 70.4% (n = 19) of European programs. The proportion was much lower in the Americas (n = 2, 9.1%) and Asia (n = 2, 22.2%), and nonexistent in Africa.

Quantitative performance data

Only 33 cervical cancer screening programs provided quantitative data. Figure 3 describes a comparative analysis of performance based on those data; details of the data by country are found in Supplementary Table 2. The screening examination coverage ranged from 2.1% in Côte d’Ivoire to 86.3% in Sweden. Substantial heterogeneity existed for screening test positivity rates, ranging from 0.5% in Sri Lanka to 7.8% in Uruguay for cytology, and from 2.3% in Kenya to 78.8% in Ethiopia for VIA. More than half of programs (n = 21, 65.6%) could not provide data on participation in further assessment. The estimated participation rate in further assessment ranged from 39.0% in Poland to 98.8% in Finland. Both detection rate and positive predictive value (PPV) could be assessed only for 12 programs providing data on final histopathological diagnosis. For programs using cytology as the primary screening method, the detection rate of CIN 2 or worse lesions (CIN 2+) ranged from 1.0 per 1,000 in Poland to 12.8 per 1,000 in Denmark.Fig. 3 Comparative values of selected performance indicators for cervical cancer screening programs that provided data to the CanScreen5 project.

The reporting format is country or region, reporting year and screening protocol. Cyto, cytology. aCuba: examination coverage might be slightly overestimated because some participants outside the screening program were screened. bRepublic of Korea: women with a previous diagnosis of cancer before the examination date were excluded from these screen-related data. cCôte d’Ivoire, Ethiopia, Morocco, Guyana, Mexico: the target population is not the total of individuals eleigible for screening (based on age); the project in Guyana is at the rolling out phase. dHungary: colposcopy was a substantial part of the screening primary visit. eNicaragua and Australia: the detection rate was only for CIN 3+. fBangladesh, Republic of Korea: the detection rate was only for cervical cancer.

Of the four cervical screening programs in Africa and one in South America that adopted a screen-and-treat protocol, only two of these programs provided data on treatment. The treatment rates for screen-positive women were 54.6% in Zimbabwe and 82.3% in Guyana.

Analysis according to World Bank income status

Unlike breast cancer screening, less variability was observed in the organization of cervical screening programs across countries belonging to different income status. An exception was the availability of diagnostic tests free of charge; while 81.0% (n = 17) of upper-middle income countries (UMICs) and 62.9% (n = 22) of HICs reported offering free diagnostic tests, only 42,1% (n = 8) of LMICs reported offering free diagnostic services. VIA was the primary cervical screening test in 50.0%, 53.8% and 4.8% of LICs, LMICs and UMICs, respectively. None of the HICs reported using VIA.

Like breast cancer screening, cervical cancer screening programs from HICs were more likely than LMICs to have an invitation system in place with an information system collecting individual data (Supplementary Table 6).

CRC screening programs

Fifty-one CRC screening programs (including regional ones) reported data for the CanScreen5 project: none from Africa; 18 from the Americas; 6 from Asia; 26 from Europe; and 1 from Oceania (Australia). Extended Data Tables 5 and 6 describe the qualitative information from CRC screening programs by continent.

Policies, protocol and organization

Most programs started in 2000 or later (n = 45, 88.2%) and used the fecal immunochemical test (FIT) for screening (n = 40, 78.4%). Colonoscopy was used as a primary screening test in Austria, Belgium, the Czech Republic, China, Germany, Greece, Turkey and Poland. The CRC screening programs were better organized than the breast or cervical cancer screening programs, with a high proportion of the programs having a dedicated budget (Americas (n = 13, 72.2%), Asia (n = 6, 100%), Europe (n = 24, 92.3%) and Australia) and provided free-of-charge screening services (Americas (n = 16, 88.9%), Asia (n = 5, 83.3%), Europe (n = 25, 96.2%) and Australia) and diagnostic services (Americas (n = 13, 72.2%), Asia (n = 4, 83.3%), Europe (n = 20, 76.9%) and Australia). Screening invitation was reported by programs in the Americas (n = 8, 44.4%), Asia (n = 2, 33.3%), Europe (n = 23, 88.5%) and Australia; 78.4% (n = 40) of the countries and regions collected individual-level screening data. Programs reporting to have links with PBCR by region were Europe (n = 16, 61.5%), Asia (n = 2, 33.3%), the Americas (n = 6, 33.3%) and Australia.

Quantitative performance data

Quantitative performance data on CRC screening was submitted by 30 programs; a comparative analysis of the key performance indicators (KPIs) is shown in Fig. 4. Data organized according to country can be found in Supplementary Table 3. Examination coverage ranged from 0.6% in Hungary to 64.5% in the Netherlands. Considerable heterogeneity was observed for screen positivity, ranging from 3.3% in France (Calvados) to 27.2% in Uruguay for FIT-based screening and from 1.8% in England (United Kingdom) to 4.1% in Latvia for guaiac fecal occult blood test (gFOBT). Further assessment participation rate ranged from 33.0% in the Republic of Korea to 97.6% in the Czech Republic. The detection rate for advanced adenoma ranged from 0.8 per 1,000 in Scotland (United Kingdom) to 80.8 per 1,000 in the Czech Republic. The detection rate of invasive cancer ranged from 0.2 per 1,000 in Australia to 9.1 per 1,000 in the Czech Republic. The Czech Republic had colonoscopy-based screening and reported the highest detection rates for both advanced adenoma and CRC.Fig. 4 Comparative values of selected performance indicators for CRC screening programs that provided data to the CanScreen5 project.

The reporting format is country or region, reporting year and screening protocol. aCzech Republic: examination coverage is underestimated in program-specific age ranges because screened persons aged over 79 are not reported. bCuba: it was not possible to separate the number of individuals screened opportunistically outside the program, thus coverage may have been overestimated.

Analysis according to World Bank income status

Only UMICs (n = 8) and HICs (n = 43) had CRC screening programs; the qualitative indicators were similar between countries. More details according to the country or region stratified by income classification are available in Supplementary Table 7.

Discussion

Screening for breast cancer, cervical cancer and CRC linked with high-quality diagnostic and treatment services demonstrated significant reduction in mortality in randomized controlled trials and ecological studies nested in real-world programs14–16. Quality assurance, defined as the process of organizing services within a health program to ensure that the outcomes meet established standards and that health benefits to the target population are maximized, is a key component of screening program organization. An expert group led by IARC in 2022 listed 16 criteria that need to be fulfilled for a screening program to be considered as well organized; these include quality assurance along with policy commitment, screening invitation, information system, screening protocol and call–recall system17. Through fulfillment of these criteria, screening programs can ensure that any inherent harms are minimized and outweighed by the potential benefits at the population level.

With an ultimate objective to improve the quality and impact of cancer screening programs, the CanScreen5 project engaged directly with screening program managers and coordinators and trained them to submit information from their own programs related to 13 of the 16 essential criteria identified by the IARC expert group (Methods). With the help of global experts, CanScreen5 also listed and defined key indicators to measure performance across the screening continuum (Supplementary Table 4). Trained participants were requested to submit data from their respective programs to enable the project to estimate these indicators. By triangulating qualitative and quantitative information, strengths and deficiencies can be identified from these programs and the values of performance indicators can be interpreted in the right context. Countries need to learn from each other to adopt best practices and correct internal deficiencies.

A public screening policy formulated through a legislative process is the strongest commitment from the government, ensuring sustained allocation of funds for screening programs18. Although mostly reported from HICs in Europe, such good practices have also been reported by countries outside Europe. The Turkish cervical screening program was launched in 2004 with a law mandating that the government must dedicate funding to provide free-of-charge HPV detection-based screening and diagnostic services. The Turkish program complied with many essential criteria of organized screening, such as invitation via text messages or phone calls (or both), active tracking of screen-positive women, a health information system collecting screening-related results and a team responsible for monitoring the program with prespecified performance indicators. In contrast, absence of a strong policy commitment and lack of assured financing (either directly or through insurance coverage) restricted the ability of many screening programs in Africa and Latin America to provide free-of-charge screening and downstream services. Consequentially, these programs suffered from low coverage, low compliance to follow-up and lack of desired impact on cancer burden. Starting in the 1980s, highly organized CRC screening programs have been implemented in some EU countries such as Italy, the Netherlands and Spain with appropriate policy, coordination, financing, screening protocol and invitation, call–recall system and quality assurance. By disseminating such good practice, CanScreen5 provides an opportunity for other programs to improve the organization and quality of their own services.

The most frequently reported performance indicator for screening programs is screening coverage. Ideally, a screening program should be population-based, indicating that the program is capable of identifying screen-eligible individuals and systematically inviting them to participate in screening. Compared to opportunistic screening, population-based screening can achieve higher coverage and ensures more equitable use of resources and higher effectiveness at the population level19. These contrasts are seen in breast cancer screening programs in the Republic of Korea and Japan, the former being a population-based one whereas the latter is opportunistic. The screening coverage reported from the Republic of Korea was 56.7% whereas the same from Japan was only 15.1%. However, having a system of invitation alone will not have the desired benefits unless downstream diagnostic and treatment services are adequately strengthened20.

The participation rate of screen-positive individuals to further assessment is a very important process indicator to monitor the quality of services and depends on whether a system of active tracking of screen-positive individuals is in place or not. The cervical screening program in Finland, with an active tracking system, achieved a further assessment participation rate of 98.8%; in the Netherlands, the rate was 76.1% without such facilities in place. Despite its high importance, our results show that most of the programs do not collect data to measure this indicator.

Measuring the detection rates of precancer or cancer (or both) is essential as an outcome indicator. The detection rate is impacted by several factors, which may not always be related to the quality of services offered. For example, the highly variable detection rates of CRC in Europe (ranging from 0.9 per 1,000 in Finland to 9.1 per 1,000 in the Czech Republic) could be attributed to differences in the screening test, the positivity cutoff value for FIT (range 15–180 μg g−1 feces) or CRC risk of the population, which is impacted by age, sex and screening prevalence. However, quality issues like further assessment compliance, which ranges from 36.3% in Belgium (Flanders) to 97.6% in the Czech Republic in Europe, and quality of diagnostic evaluation could also be responsible for low detection rates. In some instances, the gap in data quality was obvious from the indicators; for example, the detection rate of CIN 2+ in Slovenia was four times higher than that reported from Poland, despite being neighboring countries. The most likely explanation for this observation was the difference in compliance to further assessment, which was 80.7% in Slovenia and only 39.0% in Poland.

Collecting data and measuring indicators will be of value only when these are compared to expected standards, usually described as acceptable and desirable, which are often program-specific. Setting standards for the key indicators is an essential requirement for quality assurance, although this may be challenging. The performance standards for mammography screening were developed by the Breast Cancer Surveillance Consortium, including over 2 million screening mammography studies performed in over 1 million women in the United States of America, which indicated that the mean cancer detection rate and mean PPV to detect cancers are 4.7 per 1,000 and 4.8%, respectively21. The standards used in the United States of America are higher than those of more than half of the mammography programs in our study, indicating the need for setting at least some regional standards. Currently, European programs have standards for a limited number of indicators, for example, for CRC screening, participation rate to screening out of those invited, further assessment participation rate and completion rate of follow-up colonoscopy9. Collecting high-quality data on a continued basis will allow programs to set their own standards.

CanScreen5 also identified irrational policies and cancer screening practices in some countries. A decision to introduce a new screening program depends on disease burden, availability of resources, health system preparedness and prioritization of healthcare needs in the country. LMICs struggling to maintain a cervical cancer screening coverage over 10% have little justification to introduce a breast cancer screening program, as reported from Bangladesh. Kenya and South Africa continue to practice cytology-based screening despite the strong recommendation from the World Health Organization (WHO) to switch to HPV detection or VIA-based screening in settings where quality-assured cytology is difficult to implement22. Irrational practices have also been observed in HICs, for example, using colposcopy as a cervical cancer screening tool in Hungary.

An issue of concern is that many programs in our study did not have adequate quantitative data to be able to estimate the KPIs and evaluate their own quality. Among the participating programs, most could not share data beyond the number of participants screened and screen positivity. Lack of data related to further assessment of screen-positive individuals and detection of precancers or cancers may be due to logistic and financial constraints, low prioritization of quality assurance, lack of functioning information systems or hesitancy to publish ‘official’ data. Instead of collecting data from the program, LMICs mostly use data from the WHO’s STEPwise approach to surveillance surveys to report screening coverage13,23. Such data are dependent on self-reports, which are subject to recall bias24. Moreover, screening coverage correlates poorly with the impact of screening (such as reduction in mortality) as demonstrated in several Latin American countries, underscoring the need for programs to measure the performance of diagnostic and treatment services25. Building on the experience from the Canscreen5 project, cancer screening programs should consider the following measures to improve data quality and completeness: (1) conduct a thorough assessment of services associated with screening based on the information and data available; (2) identify the essential criteria for organized programs that are either missing or poorly implemented; (3) develop a feasible, measurable and time-bound plan in consultation with all stakeholders to improve the quality of services at different levels; (4) dedicate an adequate budget for quality assurance and put together a team responsible for implementing quality assurance, if not already in place; (5) build or strengthen information systems to capture performance data so that the quantitative data collection tools can be completed and KPIs can be estimated; (6) create links with population databases (for example, electoral rolls or birth registers) to be able to identify screen-eligible individuals and with PBCR to monitor impact; (7) leverage the vertical investments made to improve surveillance systems and mobile health applications to mitigate the coronavirus disease (COVID) pandemic; and (8) invest in capacity building of policymakers, managers and health professionals engaged in screening-related activities to be able to understand the value and application of quality assurance.

The CanScreen5 project has limitations. Although our ambition was to reach out to all countries and build a data repository as an IARC flagship program, that is, the Global Cancer Observatory (https://gco.iarc.fr), at this stage of the project we could only manage to collect data from a limited number of countries. As the project matures and published data become more visible, we hope to involve more countries as part of the network. The reasons for nonparticipation of some countries we approached to participate include: voluntary nature of participation (no national or global mandate); nonavailability of approval from higher authorities; and reluctance of programs to share data because of the fear of receiving criticism for poor performance. Another limitation is that the data collected from EU countries in 2016 are out of date. A new round of data collection from Europe will be initiated by IARC in 2023 to update these data. Furthermore, the quantitative data from most LMICs is very incomplete. Sometimes programs are reporting the number of examinations and tests performed and not the number of participants undergoing screening, which makes it difficult to exclude participants undergoing repeat testing within a short interval. At this stage, CanScreen5 is collecting screening data on three cancer sites for which screening is most prevalent. However, as screening for other cancer sites becomes evidence-based and is implemented, for example, lung and prostate cancers, we have plans to include these too.

The strength of the CanScreen5 project is that we have not relied on secondary data sources; instead, we collected information provided and validated by program coordinators. This global initiative collects cancer screening performance data beyond screening coverage.

In conclusion, the CanScreen5 project is a dynamic, ongoing activity and not just a one-time data collection project. We will continue with our engagement with countries, especially LMICs, to enhance data collection and quality. Investments in information technology infrastructures, high population coverage with broadband and Internet facilities, and digital capability building of the health workforce to mitigate the COVID pandemic-induced health crisis have created an enabling environment for countries to strengthen multisectoral digital healthcare26. We are optimistic that screening programs will take advantage of this accelerated digital transformation to reform the process of data collection. This will in turn improve the quality of data in CanScreen5 and make it an authentic data repository for cancer screening globally.

Methods

Overview

The CanScreen5 project was launched in June 2019 and was built on IARC’s successful reporting of the status of implementation and performance of cancer screening programs in EU Member States in collaboration with the Centro di Riferimento per l'Epidemiologia e la Prevenzione Oncologica in Piemonte, Italy and the Finnish Cancer Registry8,9. The data collection tools, KPIs and strategies for data collection and validation used in the EU project were further refined to make these tools and strategies globally relevant and suitable for different resource settings. This adaptation was done in consultation with an advisory board consisting of 21 cancer screening experts selected by IARC to represent different geographical regions and healthcare settings.

Network building and collaboration

CanScreen5 aims to collect information and data directly from each country’s Ministry of Health (MoH). IARC’s existing network of research collaborators across the globe is leveraged to reach out to the MoH. The contact person in the MoH is requested to identify program coordinators or other experts capable of providing reliable information and data. We also liaise with WHO regional offices to establish contact with the MoH. If such contact with the MoH cannot be established in a particular country, we approach the academic or public health institutes (or both) associated with the implementation and evaluation of a screening program to identify potential data providers.

Training of potential data providers

Identified data providers complete a self-paced virtual learning module. The module describes the objectives of the project, how to collect data using the data collection tools and how to submit the same online to the CanScreen5 portal. The definition of the various performance indicators and how those indicators will be estimated in the project are also explained. The e-learning modules, which are available free of charge on the IARC website (https://learning.iarc.fr/edp/courses/pgm-cancer-screening/), go beyond just describing the methodology of the project. The modules cover principles of cancer screening, planning and implementation of screening programs, and particularly focus on the principles, steps and value of quality assurance in the context of cancer screening programs. Depending on the availability of resources, we organize face-to-face workshops with groups of data providers. Data providers are given password-protected access to the data submission platform after completion of virtual learning.

Participation in the project by the countries was voluntary and no payment was made to the data providers or their staff. We tried to convince the screening program managers to invest in collecting data from their own program budget. This is important for the long-term sustainability of a project of this magnitude.

Data collection

To be able to submit data to CanScreen5, a country (or a region within the country) should have a ‘screening program’ as per the CanScreen5 definition. The project defines a screening program as one characterized by having at least a formal commitment from the health authorities to provide screening services to a defined eligible population27. This commitment must be documented as a law, an official notification or a recommendation. A documented screening protocol and a mechanism of monitoring and supervision are also required to fulfill the criteria of being a screening program.

Data providers can download the qualitative and quantitative data from the project portal, which is available in English, French, Russian and Spanish, to collect information and data from breast, cervical and CRC screening programs separately. Qualitative, freely downloadable data tools available on the portal are used to collect information on screening policies and protocols, governance and financing mechanisms, systems of invitation and recall, process of data collection for program monitoring and protocol for quality assurance. The set of data collection tools includes the corresponding guideline on each item; definitions of key terms are provided (https://canscreen5.iarc.fr/?page=datasources). Screening performance data are collected in quantitative forms across the screening continuum (from invitation to treatment), from national or regional programs. At the time of data submission, the data provider has to specify whether they are reporting for a national or a regional program. During our communications with them, after data submission, we further confirm whether the collected data reflect the entire country or a region only.

The minimum set of quantitative data requested from the programs is the number of individuals screened and the outcomes of the screening tests. Data are not processed further unless this minimum dataset is available from a program.

Data providers are advised to submit the most recent qualitative information on the screening program and quantitative data for any year within the last 5 years. Data may be submitted for multiple consecutive years, if available. Selection of the year(s) for which quantitative data are submitted is at the discretion of the data provider based on the completeness of the data (including follow-up of screen-positive individuals). A data provider who does not have quantitative data may submit only qualitative information related to the program.

Data quality checks and data validation process

Data submission by any of the data providers to the CanScreen5 data platform triggers a notification to the IARC Secretariat that initiates the internal validation to check for data consistency, completeness and validity. Submitted information is cross-verified with information available from the policy and protocol documents of the programs. The Secretariat tries to resolve any queries or discrepancies through email exchanges and virtual meetings with the data providers. The project has a scientific committee (SC) consisting of 15 international experts in the field of cancer control. The internally validated data from each country are shared with two SC members to be reviewed independently. The data provider is contacted again to resolve any queries from the SC reviewers. Virtual meetings are often organized between the project Secretariat and the team responsible for data collection from a particular screening program to finalize contents based on consensus. The final version of the validated information and data is shared with the data provider for final approval before it is made publicly available and displayed on the CanScreen5 portal. The formats used to display information include fact sheets, data tables, comparison graphs and heatmaps.

Key definitions

All the quantitative indicators have been clearly defined on the CanScreen5 portal. The numerators and denominators needed to calculate each indicator are described in Supplementary Table 4. The data used for the numerator and denominator to estimate any indicator should be collected over the same time period (a particular year(s) or one round of screening); an individual tested twice during the specified period should be counted only once during that period. Even the terms used in the qualitative data collection form have been clearly defined on the portal to ensure harmonization of data collection. Some of these key definitions are given below.

Screening program

A screening program is defined as cancer screening performed in the framework of a publicly mandated program. To be considered a ‘program’ there has to be a commitment from the government to provide the screening services to the eligible population as defined by laws, statutes, regulations or official notifications. In such cases, as a minimum, the eligible population, the screening test and the screening interval should be defined and there should be some mechanism for monitoring and supervision.

Screening policy

This is a policy for a specific screening program that specifies the government’s commitment to provide screening services and defines the targeted age and sex groups, the geographical area and other eligibility criteria; the screening test and interval; and requirements for payment or co-payment, if applicable. As a minimum, the screening protocol and repeat interval, and the determinants of eligibility for screening are stated.

Screening protocol

A screening protocol is a detailed documented plan on how to deliver the screening activities. As a minimum, the screening protocol should include clear information on eligible individuals, target age, screening test, examination intervals, further assessment, referral system and quality assurance.

Individual invitation

An individual invitation, by letter, email, text message, phone call, home visit or other method, to eligible individuals in the target population to participate in the screening program is sent by the coordination team, by primary health centers or by general practitioners.

Quality assurance

Quality assurance encompasses activities intended to assure and improve quality at all levels of the screening process to maximize benefits and cost-effectiveness while minimizing harms. It includes the assessment or evaluation of quality, the identification of problems or shortcomings in the delivery of care, the design of activities to overcome these deficiencies and follow-up monitoring to ensure the effectiveness of corrective steps. Quality assurance of the screening process requires a robust system of program management and coordination, ensuring that all aspects of the service are performing adequately.

Essential criteria for organized screening

The qualitative data collection tools collect data to assess 13 of the following 16 essential criteria identified by an IARC expert group to define organized cancer screening:17 (1) the cancer screening program has a protocol or guideline describing at least the target population, screening intervals, screening tests, referral pathway and management of positive cases; (2) there is a system in place for identifying the target population; (3) there is a system in place for inviting eligible individuals for screening; (4) the cancer screening program has a policy framework from the health authorities defining governance structure, financing, and the goals and objectives of the program; (5) performance of the screening program is evaluated with appropriate indicators; (6) the protocol or guideline at least describes monitoring and evaluation; (7) there is a system in place for notifying the results to the screened individuals and informing them about follow-up; (8) there is a system in place for sending a recall notice to noncompliant individuals; (9) the program can be audited; (10) a specified team or organization is responsible for quality assurance and improvement; (11) the performance of the cancer screening program is evaluated, published and widely disseminated on a regular basis; (12) all activities along the screening pathway are planned, coordinated and evaluated through a quality improvement framework (quality assurance); (13) there is an evidence-based protocol or guideline developed in consensus with most stakeholders; (14) an information system exists with appropriate links between population databases, screening information and cancer registries for screening implementation and evaluation; (15) the screening program has a provision for continued training for service providers; (16) the performance of the screening program is evaluated with reference standards for the indicators.The CanScreen5 project was started before we received recommendations from the IARC expert group. Hence, three indicators (6, 9 and 15) were not included in the qualitative questionnaire. These will be added in the next versions of the data collection tools.

Statistical analysis

For descriptive analysis on qualitative information, proportion (%) was used for each item according to continent (Africa, Asia, the Americas, Europe and Oceania). For performance indicators on quantitative data, examination coverage, proportion put forward for further assessment, further assessment participation rate, detection rate, PPV of the screening test and treatment rate were calculated for each program using the formulas presented in Supplementary Table 4 (using the CanScreen5 website data manager).

Ethics and inclusion statement

CanScreen5 is a global cancer screening data repository that collects data across the world, including data from LMICs. Researchers from LMICs submitting data are included as authors in the list of CanScreen5 project collaborators. We fully endorse the Nature Portfolio guidance on LMIC authorship and inclusion and we are strongly committed to the inclusion of researchers from LMICs as the CanScreen5 project moves forwards.

The CanScreen5 project is relevant to all participating countries as they provided qualitative or quantitative data (or both) on cervical, breast and CRC screening programs. Quantitative data were aggregated, covering the screening continuum from identification of the eligible population to treatment.

The IARC ethics committee reviewed the project and waived the requirement for any consent for collecting data. Data providers are mandated to ensure that they have the necessary approvals from authorities to share data.

Reporting summary

Further information on research design is available in the Nature Portfolio Reporting Summary linked to this article.

Online content

Any methods, additional references, Nature Portfolio reporting summaries, source data, extended data, supplementary information, acknowledgements, peer review information; details of author contributions and competing interests; and statements of data and code availability are available at 10.1038/s41591-023-02315-6.

Supplementary information

Supplementary Information Supplementary Tables 1–7.

Reporting Summary

Extended data

Extended Data Table 1 Information on the policy and protocol of breast cancer screening programs by continent

Information on policy and protocol of breast cancer screening programs by continent

Extended Data Table 2 Information on the organization of breast cancer screening programs by continent

Information on the organization of breast cancer screening programs by continent

Extended Data Table 3 Information on the policies and protocol of cervical cancer screening programs by continent

Information on policies and protocol of cervical cancer screening programs by continent

Extended Data Table 4 Information on the organization of cervical cancer screening programs by continent

Information on the organization of cervical cancer screening programs by continent

Extended Data Table 5 Information on the policies and protocol of colorectal cancer screening programs by continent

Information on the policies and protocol of colorectal cancer screening programs by continent

Extended Data Table 6 Information on the organization of colorectal cancer screening programs by continent

Information on the organization of colorectal cancer screening programs by continent

Extended data

is available for this paper at 10.1038/s41591-023-02315-6.

Supplementary information

The online version contains supplementary material available at 10.1038/s41591-023-02315-6.

Acknowledgements

This study is supported by the IARC intramural funding; European Union Public Health Programme (scientific and technical support to the European Partnership for Action Against Cancer and follow-up of the implementation of the Council Recommendation on Cancer Screening); Centre for Global Health Inequalities Research, Norway; American Cancer Society; National Cancer Institute, United States of America; and Medical Research Council, United Kingdom. We acknowledge all advisory board members: S. Kapambwe; S. Al-Homoud; I. Fadhil; Y. L. Qiao; R. Sankaranarayanan; A. Anttila; J. Dillner; T. Andreas Eikemo; H. de Koning; A. Ponti; S. Arrossi; R. Herrero; A. Migowski; R. Murillo; S. Luciani; D. Puricelli Perrin; L. Rabeneck; R. Smith; S. Taplin; E. L. Trimble; and K. Canfell. We acknowledge all members of the scientific committee: Y. Chami Khazraji; Z. M. Chirenje; J. Kwan Jun; K. Saika; S. Sangrajrang; F. Al Tahan; K. Zendehdel; F. Hamers; E. Kantelhardt; C. Senore; M. de Camargo Cancela; C. Ferre; E. Lazcano-Ponce; M. Saraiya; and J. O’Hallahan. We thank K. Guinot, IARC, for her support with infographic refinement, manuscript formatting and submission. Where authors are identified as personnel of IARC/WHO, the authors alone are responsible for the views expressed in this article, which do not necessarily represent the decisions, policy or views of IARC/WHO.

Author contributions

P.B. conceptualized the project. A.L.C., P.B., L.Z., I.M., E.L. and M.L.R. conducted the study. P.B., A.L.C., L.Z., I.M. and M.L.R. performed the IARC internal data validation. E.L. managed the data platform and project portal. L.Z. and P.B. drafted the manuscript. All authors provided critical comments on the manuscript and approved the final version.

Peer review

Peer review information

Nature Medicine thanks Mahdi Fallah, Muluken Gizaw, Ni Li and Anya Romanoff for their contribution to the peer review of this work. Primary Handling Editor: Ming Yang, in collaboration with the Nature Medicine team.

Data availability

The data used in this manuscript are publicly available at https://canscreen5.iarc.fr.

Code availability

No code was used for data acquisition or analysis.

Competing interests

The authors declare no competing interests.

Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

A list of authors and their affiliations appears at the end of the paper.
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References

1. World Health Organization. Cancer—Screening and Early Detection https://www.who.int/europe/news-room/fact-sheets/item/cancer-screening-and-early-detection-of-cancer (WHO, 2010).
2. Romero Y National cancer control plans: a global analysis Lancet Oncol. 2018 19 e546 e555 10.1016/S1470-2045(18)30681-8 30268693
3. Mandal R Basu P Cancer screening and early diagnosis in low- and middle-income countries: current situation and future perspectives Bundesgesundheitsblatt Gesundheitsforschung Gesundheitsschutz 2018 61 1505 1512 10.1007/s00103-018-2833-9 30353287
4. Autier P Sullivan R Population screening for cancer in high-income settings: lessons for low- and middle-income economies J. Glob. Oncol. 2019 5 1 5 30715958
5. Arbyn, M. et al. European Guidelines for Quality Assurance in Cervical Cancer Screening 2nd edn (Office for Official Publications of the European Communities, 2008).
6. Perry, N. et al. European Guidelines for Quality Assurance in Breast Cancer Screening and Diagnosis 4th edn (Office for Official Publications of the European Communities, 2006).
7. Segnan, N., Patnick, J. & von Karsa, L. European Guidelines for Quality Assurance in Colorectal Cancer Screening and Diagnosis (Office for Official Publications of the European Communities, 2010).
8. Von Karsa, L. et al. Cancer Screening in the European Union. Report on the Implementation of the Council Recommendation on Cancer Screening (European Commission, 2008).
9. Ponti, A. et al. Cancer Screening in the European Union. Report on the Implementation of Council Recommendation on Cancer Screening (European Commission, 2017).
10. Australian Institute of Health and Welfare. National Cervical Screening Program Monitoring Report 2021 (AIHW, 2021).
11. Canadian Partnership Against Cancer. Colorectal Cancer Screening in Canada: Environmental Scan https://s22457.pcdn.co/wp-content/uploads/2021/01/colorectal-cancer-screening-environmental-scan-2019-2020-Jan132021-EN.pdf (Canadian Partnership Against Cancer, 2021).
12. Secretaría de Salud México. Caminando a la Excelencia Cierre 2019 (Secretaría de Salud México, 2019).
13. Bruni L Cervical cancer screening programmes and age-specific coverage estimates for 202 countries and territories worldwide: a review and synthetic analysis Lancet Glob. Health 2022 10 e1115 e1127 10.1016/S2214-109X(22)00241-8 35839811
14. International Agency for Research on Cancer. Breast Cancer Screening. IARC Handbooks of Cancer Prevention, Vol. 15 (IARC, 2016).
15. International Agency for Research on Cancer. Colorectal Cancer Screening. IARC Handbooks of Cancer Prevention, Vol. 17 (IARC, 2019).
16. International Agency for Research on Cancer. Cervical Cancer Screening. IARC Handbooks of Cancer Prevention, Vol. 18 (IARC, 2022).
17. Zhang L An international consensus on the essential and desirable criteria for an ‘organized’ cancer screening programme BMC Med. 2022 20 101 10.1186/s12916-022-02291-7 35317783
18. World Health Organization. Screening Programmes: a Short Guide. Increase Effectiveness, Maximize Benefits and Minimize Harm (WHO Regional Office for Europe, 2020).
19. Palència L Socio-economic inequalities in breast and cervical cancer screening practices in Europe: influence of the type of screening program Int. J. Epidemiol. 2010 39 757 765 10.1093/ije/dyq003 20176587
20. Ginsburg O Breast cancer early detection: a phased approach to implementation Cancer 2020 126 2379 2393 10.1002/cncr.32887 32348566
21. Rosenberg RD Performance benchmarks for screening mammography Radiology 2006 241 55 66 10.1148/radiol.2411051504 16990671
22. World Health Organization. WHO Guidelines for Screening and Treatment of Precancerous Lesions for Cervical Cancer Prevention (WHO, 2013).
23. World Health Organization. Global Health Observatory; https://www.who.int/data/gho
24. Lemp JM Lifetime prevalence of cervical cancer screening in 55 low- and middle-income countries JAMA 2020 324 1532 1542 10.1001/jama.2020.16244 33079153
25. Murillo R Cervical cancer screening programs in Latin America and the Caribbean Vaccine 2008 26 L37 L48 10.1016/j.vaccine.2008.06.013 18945401
26. Basu P Leveraging vertical COVID-19 investments to improve monitoring of cancer screening programme—a case study from Bangladesh Prev. Med. 2021 151 106624 10.1016/j.ypmed.2021.106624 34023359
27. Basu P Status of implementation and organization of cancer screening in The European Union Member States—summary results from the second European screening report Int. J. Cancer 2018 142 44 56 10.1002/ijc.31043 28940326
