Background The English Evaluation of Daily Activity Questionnaire (EDAQ) is a patient reported measure of activity limitations including 138 activities in 14 domains. It has been linguistically and culturally validated from the original Swedish to English. In rheumatoid arthritis: confirmatory factor analysis and Rasch analysis have confirmed its internal construct validity, unidimensionality and total scores can be summed in each domain. Twelve domains can be included in two components: Self-care (Eating; Personal Care; Dressing; Cooking; Cleaning the House; Laundry; Communication) and Mobility (Bathing, Moving Indoors, Transfers, Moving Outdoors, House/Garden Maintenance). All domains demonstrate concurrent and discriminative validity, and reliability.
Objectives To test the validity and reliability of the EDAQ in people with one of seven musculoskeletal conditions (MSCs) in the UK: ankylosing spondylitis (AS); osteoarthritis (OA); systemic lupus (SLE); systemic sclerosis (SS); chronic pain (CP), chronic upper limb conditions (CUL); and Primary Sjogren's (PSS).
Methods Participants from 20 Rheumatology clinics completed postal questionnaires of demographics, the EDAQ, HAQ, SF36v2, and severity of current condition. Three weeks later, the EDAQ was repeated to evaluate test-retest reliability. Rasch analysis was used to confirm domain and component structure. Cronbach's alpha evaluated internal consistency. Spearman's correlations assessed validity of the EDAQ domains against the other measures and reliability.
Results 1205 people participated (AS n=165;OA n=184; SLE n=164; SS n=170; CP n=194; CUL n=157; PSS n=171); 942 (78%) were women; age =56.61 years (SD 13.84); condition duration =17.58 years (SD 14.45); 457 (38%) were employed; 172 (14%) had dependent children; average pain score was 4.98 (SD 3.70) and fatigue was 5.88 (SD 2.80). Rasch analysis confirmed the 12-domain, 2 component structure in all MSCs.For most conditions, most EDAQ domain scores correlated strongly with HAQ20 (rs =0.7-0.92) and at least moderately with SF36v2 Physical Functions (rs =-0.0.5 – -0.91), except in the Caring domain which were weak (rs = -0.23- -0.30) as it was applicable to few respondents. Internal consistency was good to excellent for all domains in all conditions, (α =0.82 to 0.98) meaning the EDAQ can be used for groups and individuals. Test-retest reliability (n=946, 79%) was strong for most domains (rs =0.7-0.91) except the Caring was moderate (rs =0.48-0.64). Although significant and acceptable, values were lower in CULs than other conditions. All EDAQ domains demonstrated significant (p<0.001) discriminant validity, apart from Caring (p=0.2 to 0.01).
Conclusions The English EDAQ has been shown to be a valid, reliable, multi-domain measure of daily activity in a range of musculoskeletal disorders. It can therefore be used in both clinical practice and research.
Acknowledgements This study was funded by the United Kingdom Occupational Therapy Research Fund.
Disclosure of Interest None declared