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Ann Saudi MedAnn Saudi MedAnnals of Saudi Medicine0256-49470975-4466King Faisal Specialist Hospital and Research Centre 10.5144/0256-4947.2008.60aasm-1-60aLettersReply from author Ibrahim Abdulsalam Saif Pulmonary Section, Department of Medicine Hamad Medical Corporation, Doha, Qatar, salam145@yahoo.comJan-Feb 2008 28 1 60 60 Copyright © 2008, Annals of Saudi Medicine2008This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
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I appreciate the valuable comments of Dr. Mustafa Afifi regarding the article: “Predictors of obstructive sleep apnea in snorers”, published in the November-December 2007 Annals of Saudi Medicine. The comments were noted on a few unnoticed statistical errors that happened during the preparation of the manuscript that do not affect the overall text. Please note the following corrections marked in bold:

In the abstract section: 41.5% of the female group had obstructive sleep apnea.

In the results text: OSA was seen more in non-Qatari subjects (86 of 116, 74.1%) versus [40 out of 75 (53.3%)] in Qatari subjects (P< 0.05).

In Table 1, the mean age in females in the RDI positive group is 51.8±8.2 and the RDI negative group is 50.3±10.7. The statistical analysis shown in the table compares the positive RDI group versus the negative RDI group in the same gender. The ANOVA test was used to derive the significance of age difference for males and females in the positive RDI group.

On page 424, the frequency of PSG diagnosed as OSA is 66% as mentioned in the abstract and not 72.5% as it appeared in the text.

I agree with Dr. Mustafa that we used the word “several studies” in the text without indicating references, probably just giving examples of some studies, but adding it now would not be practical. Along with this is adding discussion regarding the relation of age to the severity.

I would like to add that valuable statistical input was acknowledged in our study, though having statisticians in all steps of research would be of great help.