Background: Sleep apnea is the most pervasive sleep disorder as its severity causes even life-threatening health issues. The present study aimed to evaluate the self-administered questionnaire for assessing obstructive sleep apnea (OSA). Methods: The qualitative analysis compared and validated the Berlin (BQ), STOP-BANG (SBQ) and OSA50 questionnaires for sleep apnea assessment. In this preliminary study, we proposed four systematic analyses: gender, age group, smoking habit and working hour. One hundred and ninety participants were completed the screening test, where 52% of men and 48% of women with the mean age of 27 ± 10. Results: In the present study, the results summarized that the male, young age adults, smoking person and long working hour's participants seem to be high prevalence of OSA. The statistical parameters such as sensitivity, specificity, positive predictive values (PPV) and negative predictive values (NPV) of BQ, SBQ and OSA50 questionnaires has been calculated. The OSA50 had the highest sensitivity (93%) when compared to BQ and SBQ having the sensitivity (91%). Significant difference (p < 0.05) in specificity was found in OSA50 (93%) when compared to the specificity of BQ and SBQ (90%). The PPV and NPV of BQ and SBQ questionnaires were 24% and 77% respectively. The OSA50 achieved 65% and 98%of PPV and NPV respectively. Conclusions: The study concluded that OSA50 questionnaire seems to be better validated OSA screening tool that can be used in resource-poor primary healthcare settings. © 2020 Elsevier Ltd