validity and reliability of the short form health survey questionnaire (sf-36) for use in iranian patients with traumatic brain injury (tbi)

Background and aim: the assessment of quality of life (qol) as a measurement of traumatic brain injury (tbi) outcome can play a key role in identifying the adverse effects of tbi. there is no study on the evaluation of psychometric properties of the persian version of short form healthsurvey questionnaire (sf36) in the tbi patient population. therefore, the present study aimed to validate and test the reliability of the persian version of the sf36 in patients with tbi.methods and materials/patients: in the present crosssectional study, 185 patients with tbi were selected by nonprobability and consecutive sampling. first, the construct validity of the persian version of the sf36 questionnaire was evaluated using the confirmatory factor analysis (cfa) inamos22, and then the internal consistency reliability and itemtotal score correlation of each subscale were assessed by spss v. 22.results: results of cfa indicated that the dimensionality of sf29 questionnaire with eightfactor structure among the iranian tbi patients had construct validity (gfi=0.825, cfi=0.963, nfi=0.919, tli=0.957, rmsea=0.06) by eliminating 6 items and freeing some of the covariance errors between items, but the twofactor dimensionality (physical and psychological components of qol) of this questionnaire was not approved. internal consistency of the eightfactor form of sf29 subscales was acceptable to excellent (= alpha;0.70 to 0.99). correlation analysis of itemtotal score for determining the construct validity of sf29 indicated that except for 2 items, all items of the questionnaire had a positive and strong correlation with their subscales (r=0.40 to 0.99, p<0.0001).conclusion: persian version of sf29 with an eightfactor construct had good validity and reliability and could be used to measure healthrelated qol in iranian patients with tbi.