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10.1371/journal.pone.0289388
PONE-D-23-20966
Study Protocol
Medicine and Health Sciences
Endocrinology
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Diabetes Mellitus
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Tanzania
Prevalence of poor glycemic control and the monitoring utility of glycated albumin among diabetic patients attending clinic in tertiary hospitals in Dodoma, Tanzania: A cross-sectional study protocol
Prevalence of poor glycemic control and the monitoring utility of glycated albumin: A study protocol
https://orcid.org/0009-0004-8766-0358
Mkumbi George Gabriel Conceptualization Data curation Formal analysis Funding acquisition Investigation Methodology Project administration Resources Software Validation Visualization Writing – original draft Writing – review & editing 1 2 *
Boaz Matobogolo Conceptualization Data curation Formal analysis Funding acquisition Investigation Methodology Project administration Resources Software Supervision Validation Visualization Writing – original draft Writing – review & editing 1 2 3
1 Department of Internal Medicine, School of Medicine and Dentistry, The University of Dodoma, Dodoma, Tanzania
2 Department of Internal Medicine, Benjamin Mkapa Hospital, Dodoma, Tanzania
3 Department of Internal Medicine, University of Dodoma Hospital, Dodoma, Tanzania
mashili Fredirick Lazaro Editor
Muhimbili University of Health and Allied Sciences School of Medicine, UNITED REPUBLIC OF TANZANIA
Competing Interests: The authors have declared that no competing interests exist.

* E-mail: mkumbig@gmail.com
4 9 2024
2024
19 9 e028938817 7 2023
16 6 2024
© 2024 Mkumbi, Boaz
2024
Mkumbi, Boaz
https://creativecommons.org/licenses/by/4.0/ This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

The burden of diabetes is rising in developing countries, and this is significantly linked to the increasing prevalence of poor glycemic control. The cost of glycated haemoglobin (HbA1c) testing is a barrier to timely glycemic assessments, but newer tests such as glycated albumin may be cheaper and tempting alternatives. Additional research must ascertain if glycated albumin (GA) can act as a viable supplement or alternative to conventional HbA1c measurements for glycemic control in diabetic individuals. GA as a biomarker is an emerging area of interest, particularly for those who display unreliable HbA1c levels or cannot afford the test. This study aims to investigate the prevalence of poor glycemic control in outpatient diabetic patients and the utility of glycated albumin in this population’s monitoring of glycemic control. Method. A cross-sectional study of 203 diabetic patients will be conducted at the Dodoma Regional Referral Hospital and Benjamin Mkapa Hospital from August 1st, 2023, to August 31st, 2024. Patients diagnosed with diabetes mellitus for over six months will be screened for eligibility. Informed consent, history, clinical examination, and voluntary blood sample collection will be obtained from all eligible patients. Glycated Albumin levels will be obtained from the same blood samples collected. The glycemic status of all patients will be defined as per HbA1c, and a level of greater than 7% will considered as a poor control. The analysis will be computed with SPSS version 28.0, and a predictor variable, P<0.05, will be regarded as statistically significant, with the utility of GA determined by plotting the area under the ROC curve and the confusion matrix.

The authors received no specific funding for this work. Data AvailabilitySince this publication is a Study Protocol for a proposed study, no datasets were generated or analysed during the current publication. All relevant data from this study will be made available upon study completion in subsequent publications.
Data Availability

Since this publication is a Study Protocol for a proposed study, no datasets were generated or analysed during the current publication. All relevant data from this study will be made available upon study completion in subsequent publications.
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pmcIntroduction

Diabetes mellitus has been one of the twenty-first century’s most serious healthcare challenges [1]. The disease is spreading at an alarming rate worldwide, with developing nations accounting for 80% of the new cases [2]. In 2015, it was reported to affect 8.8 per cent (415 million) of adults worldwide, and it is expected that 652 million individuals (10.4 per cent) will have diabetes by 2040 [3]. Tanzania, like the rest of Sub-Saharan Africa, has a high diabetes burden, with rising prevalence (14.8%), complications, and death, as well as life-threatening impairments [4, 5]. According to the International Diabetes Federation (IDF), an estimated 400,000 people are living with diabetes in the country [6]. Poor glycemic control can lead to diabetic complications, which is a significant concern in diabetes management.

According to the American Diabetes Association (ADA), only 50% of patients globally achieve adequate glycemic control [7]. In sub-Saharan Africa (SSA), glycemic control rates remain suboptimal [8]. In Tanzania, recent studies have reported high rates of poor glycemic control, ranging from 67.7% to 73.8% [6, 8–10]. Managing diabetes in SSA presents many challenges, including resource inadequacies, competing traditional healthcare priorities, limited preparedness for chronic disease management, and low health insurance coverage [6, 9]. Addressing diabetes control is of paramount urgency to alleviate the mounting burden of this disease in the sub-Saharan African region. Formulating and implementing effective diabetes control strategies necessitates a comprehensive understanding of the multifaceted factors contributing to glycemic control, enabling the identification of targeted interventions [6].

To limit the risk of diabetes complications, diabetic patients must be appropriately diagnosed and monitored [11]. Diabetes diagnosis and prognosis primarily depend on two tests: serum/blood glucose and glycosylated haemoglobin (HbA1c) [12]. These metrics, however, are not failsafe, and their therapeutic utility is influenced by various clinical and analytical parameters [13]. Other glucose homeostasis markers, such as fructosamine and glycated albumin (GA), may be viewed as a desirable alternative, particularly in individuals whose HbA1c test results are inaccurate. For instance, individuals with hemoglobinopathies and kidney illness exhibit rapid alterations in glucose homeostasis and more excellent glycemic excursions [14, 15]. According to existing information, GA appears to have a higher overall diagnostic efficiency than fructosamine in various clinical contexts [16].

GA is a glycemic control indicator examined as a substitute for HbA1c in people with diabetes mellitus. GA is a far more dependable glycemic variability indicator than HbA1c. Accumulating evidence suggests that GA is a precise diagnostic test directly related to microvascular complications in diabetes [13]. Additionally, it is suitable for individuals undergoing hemodialysis, and its levels are unaffected by anaemia or haemolytic processes. GA is preferable to fructosamine because different serum proteins do not impact it differently. The catalytic technology used to analyse it is easy to deploy and quick to execute, in addition to being highly effective analytically and possessing greater standardization [17]. In clinical situations where HbA1c values are erroneously altered, GA testing may provide a reliable result for monitoring DM, according to a recent study. This is because the physiological mechanisms by which these two glycated proteins are produced guarantee that GA outperforms HbA1c in assessing glucose homeostasis without confounding factors [13].

Additional advantages of glycated albumin over glycosylated haemoglobin include decreased reagent costs and the possibility of automating glycated albumin measurement on numerous conventional laboratory instruments [18]. Although additional research is required to evaluate whether GA could augment or even replace traditional diabetic markers such as HbA1c, GA may assist in the diabetic care of patients with inaccurate HbA1c readings [19]. As a final regard to the benefits mentioned earlier of GA, an international consensus on clinical usage is required to ensure its inclusion in routine clinical laboratory workup, hence improving future monitoring and management of DM patients. Much similar research, like the one proposed, is required for this to happen.

Materials and methods

Study aims

To determine the prevalence of poor glycemic control among diabetic patients attending clinics in Dodoma Tertiary hospitals.

To determine the utility of serum glycated albumin as an index of glycemic control in diabetic patients attending clinics in Dodoma Tertiary hospitals.

Study design

For twelve months, A cross-sectional study will be conducted at the Benjamin Mkapa Hospital and the Dodoma Regional Referral Hospital in Dodoma, Tanzania.

Study setting

The medical centres at both BMH and DRRH will serve as the study sites. Dodoma, the capital city of Tanzania, is home to several medical facilities. Dodoma Regional Referral Hospital (DRRH) and Benjamin Mkapa Hospital (BMH) are both referral hospitals for the Dodoma region, the central zone, and surrounding areas, respectively. In addition, the University of Dodoma uses both hospitals as teaching centres (UDOM). These facilities partly facilitate health care for those living in the central zone. The population of the Dodoma region was 2.49 million, as per the 2012 Population and Housing Census.

BMH and DRRH have a capacity of 500 and 420 beds, respectively. Each month, approximately 1400 patients with medical-related diagnoses are seen in the medical clinics at BMH, with fifteen to twenty (15–20) of these patients having diabetes mellitus being seen every day. Additionally, 480 patients with diabetes are documented at DRRH each month. Thus, a total of 10–15 patients with diabetes mellitus are typically seen per clinic session, and a total of 30–35 patients per session from both health facilities combined (Unpublished data).

Sample size estimation

Following the Leslie-Kish formula [14, 15], the minimum sample size required to include a patient in the study will be determined as below;

Where:

N=Z2p(1−p)e2

N = Minimal sample size

Z = The value from the normal distribution scale that indicates a degree of significance (1.96 for 95% confidence level).

p = 84.3% is the rate of uncontrolled blood sugar among diabetic patients who visit the outpatient clinic [20]

e = margin of error (usually 5%) = 0.05

So; N=1.962×0.84×(0.16)

   0.052

N = 203.38 = 203

Therefore , the total sample size will be 203 participants

Inclusion criteria

Patients with at least 18 years of age.

Patients who will accept participation in the study through signing an informed consent.

Patients on oral antidiabetic drugs (OAD), insulin, or a combination of the two for at least six months.

Exclusion criteria

Patients who have received blood transfusions during the last three months.

Patients who are receiving erythropoietin.

Patients who are receiving Iron supplements.

Participants characteristics

The study participants will be adults (18 years and older) who have been diagnosed with diabetes mellitus and are attending the diabetic clinics at Benjamin Mkapa Hospital and Dodoma Regional Referral Hospital during the study period.

Sampling technique

In this study, the consecutive sampling method will be used to recruit the participants. This will enable the researcher to target and track the available patients as they visit the clinic. Therefore, the sampling technique will allow the researcher to contact any patient meeting the criteria.

Data collection process

The data collection process will begin in August 2023 until January 2024. Three research assistants will be involved and trained by the principal investigator to guarantee that the questionnaires are filled out correctly and that no research misconduct occurs during data collection. Two certified nurses and one laboratory technician will serve as researcher assistants. Each assistant interviewer will be trained to ask participants the same pertinent questions listed in the questionnaire to minimise the researcher’s bias during data collection. Respondents will be screened before the start of the clinic, and the questionnaires will be completed after informants have received service. The respondents’ names will be removed from the questionnaires, and a coding system will be used to represent their information throughout the data processing process. All responses will be kept strictly confidential and utilised for academic analysis.

Participant interview

A participant who provided informed consent will be interviewed and demographic data such as age, gender, and level of education will be collected. In addition, a minimum of two contacts, one of the patients and the second one of the next of kin, will be recorded. As part of social demographic data, alcohol consumption history (defined as alcohol consumption within the past 12 months), with an emphasis on duration and frequency, will be collected [21, 22]. In addition to the above duration and number of cigarettes in the number of packs per day, the history of current smoking, defined as smoking within the past year, will be obtained [21]. A history of hypertension (defined as a history of hypertension or the use of antihypertensive medications) and diabetes type (defined as a history of diabetes or the use of diabetic medications) will be documented [23, 24].

Laboratory procedure

Respondents will be asked to consent to a venepuncture by a trained phlebotomist at each centre. Three milliliters of blood will be drawn on either side of the cubital fossa using a 5cc syringe and placed in a red and lavender top vacutainer tube. The phlebotomist will be trained on how to handle any adverse reaction to venepuncture if they arise. The blood sample for both study blood collection centres will be transported to the authorised Benjamin Mkapa Hospital (BMH) laboratory in a refrigerated box with an ice pack for planned tests. Blood samples will be processed according to the BMH laboratory’s Standard Operating Procedures for each test.

Data collection tools

This study will use standardized, structured surveys with closed and open-ended questions to collect data as described above. The questionnaire will consist of three parts: the first will assess the patient’s sociodemographic characteristics; the second will evaluate the patient’s clinical characteristics; and the third will include laboratory results and bio data like the patient’s glycated haemoglobin and haemoglobin A1c levels, fasting blood glucose, and random blood glucose levels.

If respondents choose to complete the surveys independently, we will provide them with a Swahili translation. Enzymatic determination of GA will be performed using a liquid reagent (Lucica GA-L® Asahi Kasai Pharma Co., Tokyo, Japan) that consists of ketoamine oxidase and an albumin-specific proteinase, and the results will be evaluated using a Cobas 6000 series HPLC analyser. Automated high-performance liquid chromatography from the National Glycated Haemoglobin Standard Program and the International Federation of Clinical Chemistry will calculate the HbA1c (per cent) value.

Validity of the data collection tools

Validity will be defined as the degree to which tools or tests accurately measure what should be measured [25]. The standardized equipment and structured questions used in this study will be re-evaluated to ensure they are appropriate for the local situation and adequately assess the required variables. The draft version of the structured instrument and questions for measuring the variables will be provided to specialists from the University of Dodoma’s School of Medicine and Dentistry and the supervisors. Modifications will be made in consultation with specialists and the supervisor. During the pilot project, data-gathering tools will be pre-tested.

Reliability

The term "reliability" refers to the state of being accurate or precise and the consistency of the data gathered during the investigation [25]. The glycated haemoglobin test is considered the gold standard for monitoring glucose levels, and its sensitivity and specificity will serve as the basis for this study’s reliability (HbA1c). Additionally, structured questionnaires will be used to elicit information from informants. To guarantee the data’s reliability, the study’s tool will be pre-tested to determine its correctness and ability to produce the desired results.

Pilot study

A pilot study is defined as a smaller-scale version of a larger-scale study conducted to improve and clarify aspects of the study’s methodology, such as the tools and processes to be utilised in data gathering will be performed [26]. A pilot study aims to determine whether or not the full-scale investigation is feasible and to reveal study strengths and flaws. This study performed field testing with 10% of the minimal sample size at DRRH in mid-July. The pilot study specifically tested for adequacy, feasibility, and estimation of the time required for filling questionnaires to identify the problems that may occur during research. The information obtained from the pilot study is hoped to facilitate conducting the proposed study.

Measurements of the variables

1. Dependent variables

In this study, we will assess the serum levels of glycosylated haemoglobin (HbA1c) and glycated albumin (GA), biomarkers for determining the glycemic status in individuals with diabetes. These markers as variables will be considered the study’s dependent variables and normative values will be employed in their evaluation.

2. Independent variables

Demographic variables. Sociodemographic variables such as respondent age, gender, marital status, education, and insurance status are determined as independent variables in this study. A nominal scale will classify participants according to sex, insurance status, and marital status. Age and educational background will be presented in ordinal scales.

The patients’ clinical characteristics. Patients’ clinical profiles, such as commodity, prescription, drug adherence, and duration of illness, all have a marked influence on glycemic control and, therefore, are among the independent factors.

Data analysis plan

After data entry into the master coding sheet is complete, it will be analysed using SPSS version 28.0. The data will be cleaned and completeness checked by calculating the frequency of all variables. Descriptive statistics will be utilised to examine the demographics of the respondents. The percentage and median ages will be published, and the percentages of each gender, place of residence, degree of education, and marital status will also be shown. The percentage of those with poor glycemic control will be calculated by dividing the number of respondents with increased HbA1c values by the total number of respondents who had the test.

The findings will be shown in the form of a count (and percentage), a mean (and standard deviation), and a median (25th-75th percentiles). Comparisons of baseline characteristics between glycemic-control subgroups will be made using chi-square, analysis of variance, and Kruskal-Wallis tests. The correlation between two continuous measures will be estimated using the covariance estimate of the multivariate t distribution. This will provide some resistance to extremes without an excessively high breaking threshold. Using a single dependent variable, two correlation coefficients will be calculated and the significance of their difference will be tested using the Williams test. Segmented regression analysis will be used to examine the ties between indicators of glucose homeostasis.

This regression method generates separate regression coefficients for possible piecewise linear relations. The split point between two segmented relations will be calculated using the outcomes of Davies’ test for a non-zero difference in slope between variables. GA % and HbA1c’s ability to predict the existence of impaired glucose tolerance will be assessed and compared using the area under the receiver operating characteristic curve (AUC, C-statistic). Youden’s J-point will be used to establish diagnostic cut-offs for the different types of glucose intolerance. The Kappa statistic will be used to measure the degree of agreement between markers at these arbitrary cut-off points, and the 95% CI will be determined using 2000 replicates with stratified bootstrap and percentile approaches. These cut-offs will be used to assess the performance of GA per cent and HbA1c using the following performance measures (with a 95% confidence interval): sensitivity, specificity, Youden’s Index, positive predictive value (PPV), negative predictive value (NPV), accuracy, diagnostic odd ratio (DOR), number needed to diagnose (NND), the likelihood ratio of a positive test (LR+), and likelihood ratio of a negative test (LR-). Assuming parallel testing, we will assess the diagnostic utility of combining GA % and HbA1c. If the p-value is less than 0.05 on two-sided testing, the result is considered statistically significant with a 95% CI. Cronbach’s alpha will be used to check the data’s reliability. The study will report its findings by the Standards for the Reporting of Diagnostic Accuracy Studies (STARD).

Ethical issues

This study will follow ethical guidelines throughout the project, from participant recruitment to data collection through analysis to dissemination of results. Participants will be briefed about the study’s nature and goals and will be able to revoke their permission at any moment during the study, and will get the same level of treatment as those who choose to participate. The results of this study will be disclosed for the sole purpose of formulating an action plan. The University of Dodoma (UDOM) institutional research review ethics committee has blessed the PI’s request for ethical approval through a letter with Ref No. MA.84/261/02/9. Permission to collect the data was granted in both hospitals through a letter With Ref No. DB.122/467/01G/29 And GA.244/292/01/’E’/45 respectively. The researcher will alert the proper authorities, including attending clinicians, to follow up with respondents with laboratory findings requiring quick care.

Study timeline

This study will last for twelve calendar months, from 1st August 2023—six months of data collection, four months of data analysis, and two months for manuscript write-up.

Discussion

Glycemic monitoring is an essential part of diabetes therapy, and glycated albumin (GA) and glycated haemoglobin (HbA1c) are two typical indicators [27]. Although both help track how healthy diabetes is managed, they are measured and used clinically in different ways. Whereas HbA1c represents glucose levels on average over the previous two to three months, the usual lifespan of a red blood cell [28]. Haemoglobin beta chain glycosylation occurs when glucose covalently bonds to the amino acid valine at the N-terminal end of the beta chain [29]. Several guidelines for diagnosing and managing diabetes advocate measuring HbA1c as a benchmark [30]. Conversely, GA is generated when glucose binds to albumin without the help of an enzyme and hence represents glycemic control during the previous two to three weeks [31]. GA forms at a much quicker rate than HbA1c [32].

HbA1c and GA can be used as indicators of glycemic control, but each has unique clinical applications [17]. There is a high correlation between HbA1c levels and the risk of microvascular and macrovascular problems in diabetes, and HbA1c has been widely utilised as a marker of glycemic control in the disease [29]. The American Diabetes Association (ADA) recommends that most individuals with diabetes aim for a HbA1c of 7%, with a target of 6.5% for some patients [33, 34]. However, there are specific clinical contexts where HbA1c cannot be reliably used. HbA1c readings may be misleading, for instance, in those with hemoglobinopathies or anaemia. Haemolysis, blood transfusion, and other red blood cell turnover disorders can also affect HbA1c levels [30, 35, 36]. However, liver illness, pregnancy, and other diseases that modify albumin turnover may affect GA [36]. While HbA1c can be impacted by factors like erythrocyte turnover and drugs that shorten or lengthen the lifespan of erythrocytes, GA is unaffected by these things, and its measurement is less prone to inconsistency (6). Chronic kidney disease (CKD) patients may also benefit from GA [30, 35]. Falsely low HbA1c values in CKD patients may be caused by erythropoietin insufficiency, anaemia, and erythrocyte fragmentation [37–41]. On the other hand, GA is not influenced by these factors and may be a more reliable indicator of glycemic control in CKD patients [36].

Several studies have shown that GA levels are linked to HbA1c levels and the risk of microvascular and macrovascular complications in diabetes [32]. One study indicated that GA levels were substantially related to the danger of diabetic eye disease and kidney disease [42]. Additional research has linked elevated GA levels to type 2 diabetics’ risk of developing and experiencing severe coronary artery disease [32, 36]. A recent study also suggested that GA, rather than HbA1c, may be a more accurate predictor of cardiovascular events in those with type 2 diabetes [43].

When comparing glycated albumin to HbA1c for diabetes control, a cross-sectional study has various limitations. Uncertainty over timing, potential for bias in selection or measurement, and restricted applicability are potential limitations. Care has been taken to address these drawbacks in multiple ways, such as reducing Selection bias with careful sampling and correcting measurement bias with tried-and-true methods detailed earlier. The findings are usually more broadly applicable if they are based on a diverse and representative study population. Hence, two centres that serve a diverse group of diabetic patients from the nation’s capital were chosen. These methods aim to improve the trustworthiness and validity of the findings.

In conclusion, glycated haemoglobin (HbA1c) is the current standard marker for monitoring glycemic control, which is critical in managing diabetes [23, 44–46]. GA may offer some benefits over HbA1c in specific therapeutic settings despite HbA1c being a well-known marker with standardized measurement and documented clinical importance [23]. With a shorter half-life, more consistent measurement, and immunity to confounding factors, including erythrocyte turnover and blood transfusion, GA shows promise as a helpful marker of glycemic control in individuals with diabetes [33]. This is especially true for people whose glycemic control is less stable or who have chronic renal disease. Despite GA not being as frequently investigated as HbA1c, it has been linked in several studies to microvascular and macrovascular problems in diabetes. Therefore, the current study aims to show the actual therapeutic utility of GA and its applicability to our settings.

Supporting information

S1 Table Table showing assessment of Aim 1.

(TIF)

S2 Table Table showing assessment of Aim 2.

(TIF)

The authors would like to thank the participants, staff of Dodoma Regional Referral Hospital, and Benjamin Mkapa Hospital for donating their time to this project and the Ministry of Health.

10.1371/journal.pone.0289388.r001
Decision Letter 0
mashili Fredirick Lazaro Academic Editor
© 2024 Fredirick Lazaro mashili
2024
Fredirick Lazaro mashili
https://creativecommons.org/licenses/by/4.0/ This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Submission Version0
27 Sep 2023

PONE-D-23-20966Prevalence and monitoring utility of glycated albumin among diabetic patients attending clinic in tertiary hospitals in Dodoma, Tanzania: A cross-sectional study protocolPLOS ONE

Dear Dr. Mkumbi,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.This manuscript requires a major revision

Consider registering the study in one of clinical studies data bases like clinicaltrial.gov

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Additional Editor Comments:

The authors present a protocol of a planned study aimed at determining the prevalence and monitoring utility of glycated albumin among diabetic patients attending clinic in tertiary hospitals in Dodoma, Tanzania. The study is relevant, and the document provides a clear outline of the study's intent, methodology, and expected outcomes. The research seems well-thought-out, with comprehensive planning around data analysis and ethical considerations. Enhancements can be made in clarifying certain sections and ensuring that all potential limitations and implications are thoroughly addressed as follows.

1. A range of statistical techniques have been listed, indicating a comprehensive plan to thoroughly analyze the data. However, the authors have mentioned calculating a percentage for demographic variables (e.g., gender, place of residence). They should be cautious with smaller sample sizes as percentages may not provide a true representation. Actual counts or proportions might be more informative in such cases.

2. The inclusion of Cronbach's alpha to assess data reliability is a strong addition.

3. The research plan has clearly laid out the ethical considerations and approvals needed. It's good to see the references to consent and the process for withdrawing from the study. For completeness and clarity, the authors should consider having a plan to handle any adverse events or complications that might arise from the blood draw.

4. The timeline is straightforward. However, depending on the sample size, two months for data collection and only one month for analysis might be tight, especially if unforeseen issues arise. If that is the case the authors can consider amending their protocol based on realistic timelines and add in the protocol some of the comments raised here.

5. Comparison of GA and HbA1c is an essential part of this work. Ensure that the benefits and limitations of each are clearly demarcated and not mixed. Additionally, while the authors have addressed the clinical implications of HbA1c and GA, it may be worth briefly mentioning any cost or accessibility differences between the two, if relevant.

6. It's commendable that they have addressed potential study limitations, but consideration to adding a dedicated "Limitations" section will improve clarity.

7. The conclusion neatly sums up the relevance of the study. However, considerations to add potential implications for policy or clinical practice based on expected findings will add value.

8. The conclusion mentions the "current gold standard marker." However, a reader unfamiliar with the topic might benefit from clarifying that HbA1c is that standard marker.

9. Consider adding a statement about the potential for presenting findings at conferences or symposiums, if applicable.

10. While the hospitals and participants have been acknowledged the authors should also consider acknowledging any funding or grants that supported this work, if applicable.

11. Consider registering the study to one of clinical research data bases like clinical trial.gov

12. Lastly, they should ensure a thorough proofreading for grammatical and typographical errors before the final submission.

[Note: HTML markup is below. Please do not edit.]

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. Does the manuscript provide a valid rationale for the proposed study, with clearly identified and justified research questions?

The research question outlined is expected to address a valid academic problem or topic and contribute to the base of knowledge in the field.

Reviewer #1: No

Reviewer #2: Yes

**********

2. Is the protocol technically sound and planned in a manner that will lead to a meaningful outcome and allow testing the stated hypotheses?

The manuscript should describe the methods in sufficient detail to prevent undisclosed flexibility in the experimental procedure or analysis pipeline, including sufficient outcome-neutral conditions (e.g. necessary controls, absence of floor or ceiling effects) to test the proposed hypotheses and a statistical power analysis where applicable. As there may be aspects of the methodology and analysis which can only be refined once the work is undertaken, authors should outline potential assumptions and explicitly describe what aspects of the proposed analyses, if any, are exploratory.

Reviewer #1: Yes

Reviewer #2: Yes

**********

3. Is the methodology feasible and described in sufficient detail to allow the work to be replicable?

Descriptions of methods and materials in the protocol should be reported in sufficient detail for another researcher to reproduce all experiments and analyses. The protocol should describe the appropriate controls, sample size calculations, and replication needed to ensure that the data are robust and reproducible.

Reviewer #1: Yes

Reviewer #2: Yes

**********

4. Have the authors described where all data underlying the findings will be made available when the study is complete?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception, at the time of publication. The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: No

Reviewer #2: No

**********

5. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

Reviewer #2: No

**********

6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above and, if applicable, provide comments about issues authors must address before this protocol can be accepted for publication. You may also include additional comments for the author, including concerns about research or publication ethics.

You may also provide optional suggestions and comments to authors that they might find helpful in planning their study.

(Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: 1. The manuscript is written in the future tense while the study has already been conducted, additionally the manuscript reads like a research proposal.

2. Although there is a discussion section there are no results to be discussed.

3. Manuscript arrangement needs to follow standard journal format

4. Results and conclusion seem to be missing from abstract

5. Key references are needed, for example: “Additionally, it is suitable for individuals’ undergoing hemodialysis and its levels are unaffected by anaemia or haemolytic processes. GA is preferable to fructosamine because it is not impacted differently by different serum proteins”

Reviewer #2: GENERAL COMMENTS

1. I would advise thoroughly checking any typos and grammatical problems throughout the study protocol. This will make the proposal more comprehensible and professional-looking. For instance, glycosylated and glycated hemoglobin are mixed in various locations.

2. There are some repetitions of similar explanations in the paragraphs. This repetition can be confusing for the reader and can make the study protocol not appealing and seem less polished. Authors should thoroughly revise the whole document and make sure they remove/paraphrase wordy sentences and descriptions recurring in different sections. For example, The explanations about data collection by the use of questionnaires have been repeated several times in the text.

3. Why were other factors that may affect glycemic control like physical activity, and diet not considered.?

4. Authors should define all abbreviations the first time they are used. Also, abbreviations should be used consistently throughout the study proposal.

5. Under the Discussion section, authors should revise thoroughly and provide a reference for the applicability of cross-sectional studies in studying the Validity of diagnostic tests.

SECTIONS COMMENTS.

1. Introduction

Add a section describing the prevalence of poor glycemic control in Tanzania

2. Sample size estimation.

Can the authors provide any justification for using the cited reference from Uganda with a prevalence of 84.3%? There are a number of published studies conducted in Tanzania with a lower prevalence of poor glycemic control which would be a better choice than the one used.

3. Exclusion and Inclusion criteria

How will you identify these patients? “Patients who are at risk of receiving or donating blood”

Will the study not consider specific types of diabetic patients? E.g Type 1, type 2, autoimmune diabetes e.t.c?

4. Clinical examination

The names, brands and models, and city of manufacture of the equipment and machines should be written in brackets. For example, you write: "A blood pressure (BP) reading will be taken using an automated digital machine (AD Medical Instruments, Beijing, China)." Revise this throughout the manuscript.

5. Data collection methods.

Revise the dates for the commencement of data collection and, pilot study

In this section, it is stated that BP will be measured using a Mercury sphygmomanometer while in contrast to the previous section (clinical examination), it is clearly explained that BP will be gauged using an automated digital BP machine. To make it clear why is this so?

6. Independent variables

Revise the paragraph describing Glycemic control. what you describe is not related to the description of glycemic control as the independent variable. The paragraph is poorly organized, incoherent and congested with unnecessary explanations.

7. Ethical issues

Give a concise elaboration. Don't repeat explanations from the methodology sections.

8. Discussion

Provide a reference for the use of HbA1c a Gold standard method. A number of studies recommend OGTT as the Gold standard method.

Add more limitations of the study.

9. Dissemination of the findings

The statement “different peer-review journals for publication” should be revised. Duplicate or Salami publication is unethical in research. Manuscript should be submitted to only one peer-reviewed journal. After the previous submission's editorial decision has been made, resubmissions are permitted. .

**********

7. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy.

Reviewer #1: No

Reviewer #2: Yes: Oscar Mbembela

**********

[NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.]

While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org. Please note that Supporting Information files do not need this step.

10.1371/journal.pone.0289388.r002
Author response to Decision Letter 0
Submission Version1
11 Nov 2023

Specifically, I would like to highlight the following fundamental changes that have been made:

1. I have revised the title to enhance clarity to read as written in the subject of this letter titled response to reviewers.

2. Table 1 to 4 below Details the significant revisions and how they address the reviewers' comments in the same document.

Kindly find the attached document.

Attachment Submitted filename: Response to Reviewers.pdf

10.1371/journal.pone.0289388.r003
Decision Letter 1
mashili Fredirick Lazaro Academic Editor
© 2024 Fredirick Lazaro mashili
2024
Fredirick Lazaro mashili
https://creativecommons.org/licenses/by/4.0/ This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Submission Version1
24 Jan 2024

PONE-D-23-20966R1PREVALENCE OF POOR GLYCEMIC CONTROL AND THE MONITORING UTILITY OF GLYCATED ALBUMIN AMONG DIABETIC PATIENTS ATTENDING CLINIC IN TERTIARY HOSPITALS IN DODOMA, TANZANIA: A CROSS-SECTIONAL STUDY PROTOCOLPLOS ONE

Dear Dr. Mkumbi,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

Please address the comments raised by one of the reviewersThis manuscript requires a minor revision

Please format your manuscript accordingly 

Please submit your revised manuscript by Mar 09 2024 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file.

Please include the following items when submitting your revised manuscript:A rebuttal letter that responds to each point raised by the academic editor and reviewer(s). You should upload this letter as a separate file labeled 'Response to Reviewers'.

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We look forward to receiving your revised manuscript.

Kind regards,

Fredirick Lazaro mashili, MD, PhD

Academic Editor

PLOS ONE

Journal Requirements:

Please review your reference list to ensure that it is complete and correct. If you have cited papers that have been retracted, please include the rationale for doing so in the manuscript text, or remove these references and replace them with relevant current references. Any changes to the reference list should be mentioned in the rebuttal letter that accompanies your revised manuscript. If you need to cite a retracted article, indicate the article’s retracted status in the References list and also include a citation and full reference for the retraction notice.

Additional Editor Comments:

Please address the comments raised by one of the reviewers

[Note: HTML markup is below. Please do not edit.]

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. Does the manuscript provide a valid rationale for the proposed study, with clearly identified and justified research questions?

The research question outlined is expected to address a valid academic problem or topic and contribute to the base of knowledge in the field.

Reviewer #2: Yes

Reviewer #3: Yes

**********

2. Is the protocol technically sound and planned in a manner that will lead to a meaningful outcome and allow testing the stated hypotheses?

The manuscript should describe the methods in sufficient detail to prevent undisclosed flexibility in the experimental procedure or analysis pipeline, including sufficient outcome-neutral conditions (e.g. necessary controls, absence of floor or ceiling effects) to test the proposed hypotheses and a statistical power analysis where applicable. As there may be aspects of the methodology and analysis which can only be refined once the work is undertaken, authors should outline potential assumptions and explicitly describe what aspects of the proposed analyses, if any, are exploratory.

Reviewer #2: Yes

Reviewer #3: Yes

**********

3. Is the methodology feasible and described in sufficient detail to allow the work to be replicable?

Descriptions of methods and materials in the protocol should be reported in sufficient detail for another researcher to reproduce all experiments and analyses. The protocol should describe the appropriate controls, sample size calculations, and replication needed to ensure that the data are robust and reproducible.

Reviewer #2: Yes

Reviewer #3: Yes

**********

4. Have the authors described where all data underlying the findings will be made available when the study is complete?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception, at the time of publication. The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #2: Yes

Reviewer #3: Yes

**********

5. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #2: Yes

Reviewer #3: Yes

**********

6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above and, if applicable, provide comments about issues authors must address before this protocol can be accepted for publication. You may also include additional comments for the author, including concerns about research or publication ethics.

You may also provide optional suggestions and comments to authors that they might find helpful in planning their study.

(Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #2: Extensive revisions have been made by the authors as it was suggested. I would therefore recommend accepting the manuscript for publication

Reviewer #3: REVIEWER COMMENTS

The authors intend to determine the prevalence of poor glycemic control and the utility of serum glycated albumin (GA) as an index of glycemic control in diabetic patients. The proposed study is important since GA appears to be of great potential in diagnostic efficiency, relatively less costly and the possibility of GA equipment automation. In turn, GA as biomarker for glycemic control will be useful in limited resource settings such as Tanzania.

Nevertheless, the authors need to address the following comments;

1. It is not clear why the authors will screen for eligibility among patients diagnosed with diabetes mellitus for over six months. What was the basis for using 6 months as a cut-f point for eligibility to participate in the study?

2. The authors intend to conduct an interview and self-administer the questionnaire among those would wish to do so. In addition, those wishing to self-administer the question will be given a Swahili version questionnaire. How is this likely to affect the study findings?

3. The authors describe that they will perform physical examinations and/or obtain information such as blood pressure, body mass index and electrocardiogram. However, the relationship between such parameters and the validity of GA in glycemic control is not clearly described in the introduction and methods section such as in the analysis section.

**********

7. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy.

Reviewer #2: Yes: Oscar Mbembela

Reviewer #3: No

**********

[NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.]

While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org. Please note that Supporting Information files do not need this step.

Attachment Submitted filename: REVIEWER COMMENTS.pdf

10.1371/journal.pone.0289388.r004
Author response to Decision Letter 1
Submission Version2
21 Mar 2024

comment 1: It is not clear why the authors will screen for eligibility among patients diagnosed with diabetes mellitus for over six months. What was the basis for using 6 months as a cut-off point for eligibility to participate in the study?

response1 : • The six-month period has no meaning and was chosen arbitrarily just to exclude new and unstable diabetic patients from participating in the study while targeting stable anti-diabetic medication clients that have been at least on medication for some time and are assumed to have a set regimen that they adhere to. This aligns with the goal of the study to estimate glycemic control and suggest a better test, rather than to diagnose the disease.

comment 2: The authors intend to conduct an interview and self-administer the questionnaire among those would wish to do so. In addition, those wishing to self-administer the question will be given a Swahili version questionnaire. How is this likely to affect the study findings?

response 2: • It is the author's view that the questionnaires to be as simple and clear that an individual with basic reading and writing can understand and fill them accurately with no or minimal assistance, in a language that is native and common in the study area. It is our view that when this chance is granted it improves participation rates and lowers the data collection burden. With proper proofreading and review of all submissions, it's unlikely to affect the results finding.

comment 3: The authors describe that they will perform physical examinations and/or obtain information such as blood pressure, body mass index, and electrocardiogram. However, the relationship between such parameters and the validity of GA in glycemic control is not clearly described

response 3: • The author acknowledges the fact that this was an unnecessary undertaking and it is removed from the methodology section.

Attachment Submitted filename: Response to Reviweres.docx

10.1371/journal.pone.0289388.r005
Decision Letter 2
mashili Fredirick Lazaro Academic Editor
© 2024 Fredirick Lazaro mashili
2024
Fredirick Lazaro mashili
https://creativecommons.org/licenses/by/4.0/ This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Submission Version2
19 Jun 2024

PREVALENCE OF POOR GLYCEMIC CONTROL AND THE MONITORING UTILITY OF GLYCATED ALBUMIN AMONG DIABETIC PATIENTS ATTENDING CLINIC IN TERTIARY HOSPITALS IN DODOMA, TANZANIA: A CROSS-SECTIONAL STUDY PROTOCOL

PONE-D-23-20966R2

Dear Dr. Mkumbi,

We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements.

Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication.

An invoice will be generated when your article is formally accepted. Please note, if your institution has a publishing partnership with PLOS and your article meets the relevant criteria, all or part of your publication costs will be covered. Please make sure your user information is up-to-date by logging into Editorial Manager at Editorial Manager® and clicking the ‘Update My Information' link at the top of the page. If you have any questions relating to publication charges, please contact our Author Billing department directly at authorbilling@plos.org.

If your institution or institutions have a press office, please notify them about your upcoming paper to help maximize its impact. If they’ll be preparing press materials, please inform our press team as soon as possible -- no later than 48 hours after receiving the formal acceptance. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact onepress@plos.org.

Kind regards,

Fredirick Lazaro mashili, MD, PhD

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

The authors have sufficiently addressed all the comments raised by the reviewers.

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. Does the manuscript provide a valid rationale for the proposed study, with clearly identified and justified research questions?

The research question outlined is expected to address a valid academic problem or topic and contribute to the base of knowledge in the field.

Reviewer #3: Yes

**********

2. Is the protocol technically sound and planned in a manner that will lead to a meaningful outcome and allow testing the stated hypotheses?

The manuscript should describe the methods in sufficient detail to prevent undisclosed flexibility in the experimental procedure or analysis pipeline, including sufficient outcome-neutral conditions (e.g. necessary controls, absence of floor or ceiling effects) to test the proposed hypotheses and a statistical power analysis where applicable. As there may be aspects of the methodology and analysis which can only be refined once the work is undertaken, authors should outline potential assumptions and explicitly describe what aspects of the proposed analyses, if any, are exploratory.

Reviewer #3: Yes

**********

3. Is the methodology feasible and described in sufficient detail to allow the work to be replicable?

Descriptions of methods and materials in the protocol should be reported in sufficient detail for another researcher to reproduce all experiments and analyses. The protocol should describe the appropriate controls, sample size calculations, and replication needed to ensure that the data are robust and reproducible.

Reviewer #3: Yes

**********

4. Have the authors described where all data underlying the findings will be made available when the study is complete?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception, at the time of publication. The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #3: Yes

**********

5. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #3: Yes

**********

6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above and, if applicable, provide comments about issues authors must address before this protocol can be accepted for publication. You may also include additional comments for the author, including concerns about research or publication ethics.

You may also provide optional suggestions and comments to authors that they might find helpful in planning their study.

(Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #3: The manuscript is well written and the methodology is valid.

Nevertheless, the authors have responded that... "The six-month period has no meaning and was chosen arbitrarily just to exclude new and unstable diabetic patients from participating in the study while targeting stable anti-diabetic medication clients that have been at least on medication for some time and are assumed to have a set regimen that they adhere to. This aligns with the goal of the study to estimate glycemic control and suggest a better test, rather than to diagnose the disease."

Therefore, it is my opinion that such reasoning needs to be incorporated in the discussion section to enable the readers understand why the cut-off point for inclusion was set to be six months, and possibly state how this is likely to or not affect the study findings.

**********

7. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy.

Reviewer #3: Yes: Alexander Mtemi Tungu

**********
==== Refs
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13 Belinskaia DA , Voronina PA , Goncharov N V . Integrative Role of Albumin: Evolutionary, Biochemical and Pathophysiological Aspects. J Evol Biochem Physiol. 2021;57 : 1419–1448. doi: 10.1134/S002209302106020X 34955553
14 Doumatey AP , Feron H , Ekoru K , Zhou J , Adeyemo A , Rotimi CN . Serum fructosamine and glycemic status in the presence of the sickle cell mutation. Diabetes Res Clin Pract. 2021;177 : 108918. doi: 10.1016/j.diabres.2021.108918 34126128
15 Bloomgarden Z , Handelsman Y . How does CKD affect HbA1c? Pubmed. 2018;10 : 1–2. doi: 10.1111/1753-0407.12624 29124865
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17 Freitas PAC , Ehlert LR , Camargo JL . Glycated albumin: A potential biomarker in diabetes. Arch Endocrinol Metab. 2017;61 : 296–304. doi: 10.1590/2359-3997000000272 28699985
18 Xiong J , Wang J , Zhao X , Yang C , Jiang X , Chen Y . Glycated albumin as a biomarker for diagnosis of diabetes mellitus: A systematic review and meta-analysis. World J Clin Cases. 2021;9 : 9520–9535. doi: 10.12998/wjcc.v9.i31.9520 34877286
19 George C , Matsha TE , Korf M , Zemlin AE , Erasmus RT , Kengne AP . The agreement between fasting glucose and markers of chronic glycaemic exposure in individuals with and without chronic kidney disease: a cross-sectional study. 2020; 1–11.
20 Patrick NB , Yadesa TM , Muhindo R , Lutoti S . Poor glycemic control and the contributing factors among type 2 diabetes mellitus patients attending outpatient diabetes clinic at Mbarara Regional Referral Hospital, Uganda. Diabetes Metab Syndr Obes. 2021;14 : 3123–3130. doi: 10.2147/DMSO.S321310 34262316
21 Whelton PK , Carey RM , Aronow WS , Casey DE , Collins KJ , Dennison Himmelfarb C , et al . 2017 ACC/AHA/AAPA/ABC/ACPM/AGS/APhA/ASH/ASPC/NMA/PCNA Guideline for the Prevention, Detection, Evaluation, and Management of High Blood Pressure in Adults: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Pr. J Am Coll Cardiol. 2018;71 : e127–e248. doi: 10.1016/j.jacc.2017.11.006 29146535
22 January CT , Wann LS , Calkins H , Chen LY , Cigarroa JE , Cleveland JC , et al . 2019 AHA/ACC/HRS Focused Update of the 2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines and the Heart Rhythm Society. J Am Coll Cardiol. 2019;74 : 104–132. doi: 10.1016/j.jacc.2019.01.011 30703431
23 Feldman H , ElSayed NA , McCoy RG , Moverley J , Oser SM , Segal AR , et al . Standards of Care in Diabetes—2023 Abridged for Primary Care Providers. Clinical Diabetes. 2023;41 : 4–31. doi: 10.2337/CD23-AS01/148029/STANDARDS-OF-CARE-IN-DIABETES-2023-ABRIDGED-FOR
24 Rajkumar A , Bhattacharjee A , Selvaraj R . Diagnostic accuracy of apex-pulse deficit for detecting atrial fibrillation. International Journal of Advanced Medical and Health Research. 2019;6 : 52. doi: 10.4103/IJAMR.IJAMR_48_19
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