title: Reliability and validity of the telephone administration of the wheelchair outcome measure (WhOM) for middle-aged and older users of power mobility devices.
abstract: OBJECTIVE
  To examine the measurement properties of the tele-phone administration of the Wheelchair Outcome Measure (WhOM).
  
  
  METHODS
  Power mobility device users aged 50-89 years.
  
  
  METHODS
  Two independent cohorts were recruited: (i) a prospective cohort (n = 40) to estimate test-retest reliability and to determine the applicability of the telephone format, and (ii) a cross-sectional cohort to examine construct validity with 3 groups: (a) people waiting for a first power mobility device (n = 44); (b) initial users (n = 35; 1-6 months); and (c) long-term users (n = 39; 12-18 months).
  
  
  RESULTS
  The tool demonstrated good test-retest reliability (intraclass correlation coefficient 0.77-1.00), took 10.9 min (standard deviation = 5.2) to administer and was practical to use over the telephone. Validity testing showed moderate correlations with the Quebec User Evaluation of Satisfaction with Technology (rS = 0.36-0.45) and the Psychosocial Impact of Assistive Devices Scale (rS = 0.31-0.43). WhOM scores could discriminate non-users from users (wait-list vs initial users; wait-list vs long-term users, p < 0.001) and power wheelchair from scooter users (total WhOM scores, p < 0.05).
  
  
  CONCLUSIONS
  The WhOM is a stable, valid and applicable measure for telephone administration with older power mobility device users. It is moderately linked to satisfaction with the device and to the psychosocial impact of the device, and therefore complements rather than replaces those measures.
authors.affiliation: Research Centre, Institut universitaire de gériatrie de Montréal, 4565 Queen Mary Road, Montréal, Quebec, Canada. claudine.auger@mail.mcgill.ca
authors.forename: Claudine
authors.initials: C
authors.lastname: Auger
authors.forename: Louise
authors.initials: L
authors.lastname: Demers
authors.forename: Isabelle
authors.initials: I
authors.lastname: Gélinas
authors.forename: François
authors.initials: F
authors.lastname: Routhier
authors.forename: W Ben
authors.initials: WB
authors.lastname: Mortenson
authors.forename: William C
authors.initials: WC
authors.lastname: Miller
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D006233:Persons with Disabilities / Q000523:psychology / Q000534:rehabilitation*; D011211:Electric Power Supplies; D004867:Equipment Design; D006801:Humans; D008875:Middle Aged; D051346:Mobility Limitation; D017063:Outcome Assessment, Health Care / Q000379:methods; D017060:Patient Satisfaction; D015203:Reproducibility of Results; D012656:Self-Help Devices; D011795:Surveys and Questionnaires; D013689:Telephone; D014910:Wheelchairs