title: Stability of physical assessment of older drivers over 1 year.
abstract: Older adults represent the fastest-growing population of drivers with a valid driver's licence. Also common in this age group are multiple chronic medical conditions that may have an effect on physical function and driving ability. Determining the reliability of physical measures used to assess older drivers' functional ability is important to identifying those who are safe to continue driving. Most previous reliability studies of clinical physical measures of health used test-retest intervals shorter than those between patient visits with a clinician. In the present study we examined a more clinically representative interval of 1 year to determine the stability of commonly used physical measures collected during the Candrive II prospective cohort study of older drivers. Reliability statistics indicate that the sequential finger-thumb opposition, rapid pace walk and the Pelli-Robson contrast sensitivity tests have adequate stability over 1 year. Poor stability was observed for the one-legged stance and Snellen visual acuity test. Several assessments with nominal data (Marottoli method [functional neck range of motion], whispered voice test, range of motion and strength testing) lacked sufficient variability to conduct reliability analyses; however, a lack of variability between test days suggests consistency over a 1-year time frame. Our results provide evidence that specific physical measures are stable in monitoring functional ability over the course of a year.
authors.affiliation: Ottawa Hospital Research Institute, University of Ottawa, Ottawa, Ont., Canada. Electronic address: smarshall@ottawahospital.on.ca.
authors.forename: Andrew
authors.initials: A
authors.lastname: Smith
authors.forename: Shawn
authors.initials: S
authors.lastname: Marshall
authors.forename: Michelle
authors.initials: M
authors.lastname: Porter
authors.forename: Linda
authors.initials: L
authors.lastname: Ha
authors.forename: Michel
authors.initials: M
authors.lastname: Bédard
authors.forename: Isabelle
authors.initials: I
authors.lastname: Gélinas
authors.forename: Malcolm
authors.initials: M
authors.lastname: Man-Son-Hing
authors.forename: Barbara
authors.initials: B
authors.lastname: Mazer
authors.forename: Mark
authors.initials: M
authors.lastname: Rapoport
authors.forename: Holly
authors.initials: H
authors.lastname: Tuokko
authors.forename: Brenda
authors.initials: B
authors.lastname: Vrkljan
mesh_terms: D000203:Activities of Daily Living; D000368:Aged; D000369:Aged, 80 and over; D001334:Automobile Driving / Q000706:statistics & numerical data*; D005080:Exercise Test / Q000706:statistics & numerical data*; D005260:Female; D015577:Geriatric Assessment / Q000706:statistics & numerical data*; D006320:Hearing Tests / Q000706:statistics & numerical data*; D006801:Humans; D008297:Male; D053580:Muscle Strength; D010808:Physical Examination / Q000706:statistics & numerical data*; D016059:Range of Motion, Articular; D015203:Reproducibility of Results; D014787:Vision Tests / Q000706:statistics & numerical data*
keywords: Older drivers; Physical measures; Stability