title: Reliability and validity of the Assessment of Daily Activity Performance (ADAP) in community-dwelling older women.
abstract: OBJECTIVE
  The Assessment of Daily Activity Performance (ADAP) test was developed, and modeled after the Continuous-scale Physical Functional Performance (CS-PFP) test, to provide a quantitative assessment of older adults' physical functional performance. The aim of this study was to determine the intra-examiner reliability and construct validity of the ADAP in a community-living older population, and to identify the importance of tester experience.
  
  
  METHODS
  Forty-three community-dwelling, older women (mean age 75 yr +/-4.3) were randomized to the test-retest reliability study (n=19) or validation study (n=24). The intra-examiner reliability of an experienced (tester 1) and an inexperienced tester (tester 2) was assessed by comparing test and retest scores of 19 participants. Construct validity was assessed by comparing the ADAP scores of 24 participants with self-perceived function by the SF-36 Health Survey, muscle function tests, and the Timed Up and Go test (TUG).
  
  
  RESULTS
  Tester 1 had good consistency and reliability scores (mean difference between test and retest scores (DIF), -1.05+/-1.99; 95% confidence interval (CI), -2.58 to 0.48; Cronbach's alpha (alpha) range, 0.83 to 0.98; intraclass correlation (ICC) range, 0.75 to 0.96; Limits of Agreement (LoA), -2.58 to 4.95). Tester 2 had lower reliability scores (DIF, -2.45+/-4.36; 95% CI, -5.56 to 0.67; alpha range, 0.53 to 0.94; ICC range, 0.36 to 0.90; LoA, -6.09 to 10.99), with a systematic difference between test and retest scores for the ADAP domain lower-body strength (-3.81; 95% CI, -6.09 to -1.54), ADAP correlated with SF-36 Physical Functioning scale (r=0.67), TUG test (r=-0.91) and with isometric knee extensor strength (r=0.80).
  
  
  CONCLUSIONS
  The ADAP test is a reliable and valid instrument. Our results suggest that testers should practise using the test, to improve reliability, before applying it to clinical settings.
authors.affiliation: Mobility Laboratory, Department of Geriatric Medicine, University Medical Center, Utrecht, The Netherlands. paul.devreede@tno.nl
authors.forename: Paul L
authors.initials: PL
authors.lastname: de Vreede
authors.forename: Monique M
authors.initials: MM
authors.lastname: Samson
authors.forename: Nico L
authors.initials: NL
authors.lastname: van Meeteren
authors.forename: Sijmen A
authors.initials: SA
authors.lastname: Duursma
authors.forename: Harald J
authors.initials: HJ
authors.lastname: Verhaar
mesh_terms: D000203:Activities of Daily Living; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D003625:Data Collection; D005260:Female; D015577:Geriatric Assessment / Q000379:methods*; D006304:Health Status; D006801:Humans; D051346:Mobility Limitation; D053580:Muscle Strength / Q000502:physiology; D015588:Observer Variation; D015203:Reproducibility of Results; D012649:Self Concept