title: Concurrent validity and reliability of clinical evaluation of the single leg squat.
abstract: This study determined reliability and concurrent validity of measurements of the single leg squat made by novice examiners. Twelve video recordings of individuals performing a single leg squat were evaluated by six student physical therapists. Students assessed movement quality on an ordinal scale and manually measured frontal plane knee movement quantity on a video monitor. Inter- and intrarater reliability of ordinal scale ratings were determined via quadratically weighted kappa. Inter- and intrarater reliability of frontal plane knee measures were determined through intraclass correlation coefficient models 2,k and 3,k (k = 3 ratings), respectively. Concurrent validity of frontal plane knee measures was examined by comparison with Vicon-Peak motion-tracking system measures via Bland-Altman scatterplots. Ordinal scale measures displayed intrarater reliability ranging from 0.38 to 0.94 and interrater reliability of 0.68 (0.46-0.87). Intrarater reliability of frontal plane knee measures ranged from 0.88 to 0.98 and interrater reliability of 0.99 (0.97-1.00). Difference scores between student and computer-generated measures of frontal plane knee movement were significantly different as determined through Bland-Altman scatterplots and calculation of the upper and lower limits of agreement.
authors.affiliation: Center for Rehabilitation Research, Texas Tech University Health, Sciences Center, Lubbock, Texas, USA. dpoulsen@rocketmail.com
authors.forename: Daniel R
authors.initials: DR
authors.lastname: Poulsen
authors.forename: C Roger
authors.initials: CR
authors.lastname: James
mesh_terms: D000328:Adult; D053587:Arthrometry, Articular; D006801:Humans; D007719:Knee Joint / Q000502:physiology*; D018482:Muscle, Skeletal / Q000502:physiology*; D015203:Reproducibility of Results; D013336:Students, Health Occupations; D014741:Video Recording