Dear Editor-in-Chief

We read with great interest the article published in JRHS journal by Lotfi et al.¹ They discussed on the Prevalence of Diabetes in People aged ≥30 years using Results of Screening Program in Yazd Province. Authors found that prevalence of diabetes in women (25.3%) was more than men (9.2%). It seems that High prevalence of type 2 diabetes in women due to the large portion (more than 90 percent) of women who have participated in the study were 50 years and above. In other words, the mean age of women was higher than men (Table 2¹; diabetic women = 1235, total number of diabetic patients ≥50 years = 1206). If this is confirmed by the authors, the high prevalence of diabetes among women in present study is due to selection bias and not volunteer bias that has cited in the discussion. In fact, it was better that sampling was done better, or analysis should be standardized based on province or national population. Authors only in this way could claim that obtained measurements in the study are related to people aged ≥30 yr. Thus, the prevalence of diabetes in the general population and in subgroups (gender) will differ from the reported facts and figures.