en Epidemiology Epidemiology Original Research Original Research <strong>Background: </strong>The present study was conducted to translate and validate the World Health Organization&rsquo;s Quality-of-Life Scale -BREF into local language of Pakistan.&nbsp;&nbsp;<br> <strong>&nbsp;&nbsp; Methods:</strong> A forward- backward translation procedure was followed to develop the Pakistani version of the questionnaire. Through a multi- stage clustered sampling technique, a sample of individuals aged 18 years and above completed the questionnaire in Abbottabad district, Pakistan. Psychometric properties of the instrument including reliability (internal consistency and test-retest analysis), validity (known group comparison and items&rsquo; correlation) and their domains were assessed. Satisfactory results were also shown in the correlation matrix in all domains.<br> <strong>&nbsp;&nbsp; Results:</strong> A total of 2060 participants were recruited in this study. Participants&rsquo; mean age was 35.51 (SD= 14.31) years in healthy individuals and 39.29 (SD= 14.31) years in diseased individuals. The internal consistency of the WHOQOL-BREF (Pakistani Version) was 0.86. Moreover, the physical, psychological, and environmental domains had acceptable reliability (alpha= 0.78, 0.75, and 0.73, respectively), but reliability was low (alpha= 0.56) in the social domain. Reproducibility of the WHOQOL-BREF was as follows: ICC range: 0.72&ndash;0.92 at 2-week retest interval. After performing comparison analysis, the results indicated that the questionnaire significantly segregated the study groups in all QoL domains, except for social relationship.<br> <strong>&nbsp;&nbsp; Conclusion:</strong> The study provided strong exploratory evidence for the reliability and validity of the WHOQOL-BREF for use in Pakistan. However, more exploration is needed to improve the reliability results in the social domain.&nbsp; Reliability, Quality of life, Validity, Pakistan, WHOQOL-BREF 853 859 http://mjiri.iums.ac.ir/browse.php?a_code=A-10-3620-1&slc_lang=en&sid=1 Fahad Saqib Lodhi fahadsaqiblodhi@hotmail.com 200319475328460035589 200319475328460035589 No Department of Epidemiology and Biostatistics, School of Public Health, International Campus, Tehran University of Medical Sciences (IC-TUMS), Tehran, Iran. Owais Raza ow.raza@hotmail.com 200319475328460035590 200319475328460035590 No Department of Epidemiology and Biostatistics, School of Public Health, International Campus, Tehran University of Medical Sciences (IC-TUMS), Tehran, Iran. Ali Montazeri montazeri@acecr.ac.ir 200319475328460035591 200319475328460035591 No Institute for Health Sciences Research, Academic Center for Education, Culture and Research, Tehran, Iran. Saharnaz Nedjat nejatsan@tums.ac.ir 200319475328460035592 200319475328460035592 No Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran Mehdi Yaseri m.yaseri@gmail.com 200319475328460035593 200319475328460035593 No Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran Kourosh Holakouie-Naieni 200319475328460035594 200319475328460035594 Yes Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran