Adaptation, reliability and validity testing of a Persian version of the Health Assessment Questionnaire-Disability Index in Iranian patients with rheumatoid arthritis.
OBJECTIVE
The aim of the present study was to culturally adapt and evaluate reliability and validity of Health Assessment Questionnaire-Disability Index (HAQ-DI) in Iranian patients with rheumatoid arthritis (RA).


METHODS
234 patients with RA for validation study, Eighty-six participants for reliability study.


METHODS
Test-retest relative reliability and internal consistency of Persian version of HAQ-DI were examined by intraclass correlation coefficient (ICC) and Cronbach's alpha, respectively. Additionally, HAQ-DI construct validity (Spearman's correlation) was examined using Persian version of Short-Form 36 Health survey (SF-36), activity and severity parameters.


RESULTS
Persian version of HAQ-DI total score showed excellent test-retest reliability (ICC = 0.98) and internal consistency (Cronbach's alpha = 0.95). Spearman's correlations between the total PHAQ-DI score and activity and severity parameters were above 0.55. Correlation between PHAQ-DI and SF-36 Physical Health were higher as compared with SF-36 Mental Health.


CONCLUSIONS
Persian version of HAQ-DI is a reliable and valid culturally-adapted instrument in order to measure functional limitations in Iranian people with RA.
Department of Physical Therapy, School of Paramedical Sciences, Mashhad University of Medical Sciences, Vakil abad Blvd, Bahonar Blvd, Pardis campus, Mashhad, Iran. Electronic address: Nazary_salman@yahoo.com.
Salman
S
Nazary-Moghadam
Department of Physical Therapy, Faculty of Rehabilitation Sciences, Tehran University of Medical Sciences, Enghelab Avenue, Tehran, Iran. Electronic address: A_zeinalzade@yahoo.com.
Afsaneh
A
Zeinalzadeh
Department of Physiotherapy, University of Social Welfare and Rehabilitation Sciences, Koodakyar Ave, Daneshjoo Blvd, Evin, Tehran, Iran. Electronic address: mahyarsalavati@gmail.com.
Mahyar
M
Salavati
Department of Rheumatology, Rheumatology Research Center, Firoozgar Hospital, Iran University of Medical Sciences (IUMS), Tehran, Iran. Electronic address: Simin_almasi@yahoo.com.
Simin
S
Almasi
Department of Physical Therapy, School of Paramedical Sciences, Mashhad University of Medical Sciences, Vakil abad Blvd, Bahonar Blvd, Pardis campus, Mashhad, Iran. Electronic address: honegahban@yahoo.com.
Hossein
H
Negahban
D000203:Activities of Daily Living; D000328:Adult; D000368:Aged; D001172:Arthritis, Rheumatoid / Q000534:rehabilitation*; D004185:Disability Evaluation; D005260:Female; D006801:Humans; D007492:Iran; D008297:Male; D008875:Middle Aged; D026741:Physical Therapy Modalities / Q000592:standards*; D011594:Psychometrics; D011788:Quality of Life; D015203:Reproducibility of Results; D011795:Surveys and Questionnaires / Q000592:standards*
Arthritis; Face validity; Iran; Rheumatoid; Test-retest reliability; Translations