An assessment of the health assessment questionnaire functional ability index among women with systemic lupus erythematosus

Abstract. The validity of the Health Assessment Questionnaire (HAQ) functional ability instrument was tested in 120 women with definite systemic lupus erythematosus (SLE) from rheumatology clinics at 2 local tertiary care institutions. Reliability and validity results for this population of women (mean age: 41 years±13; age at diagnosis 33 years±13) indicate that (1) the HAQ was internally reliable (standardized alpha = 0.9443) with no interitem correlation exceeding (r=0.75); (2) confirmatory factor analysis identified 2 predominant factors among the HAQ components suggestive of large limb gross movements (e.g., walking, arising) and small limb fine movements (e.g., the ability to eat and firmly grip objects)