title: Validity of self-reporting and video-recording for measuring knee-straining work postures.
abstract: The aim of this study was to compare the validity of self-reporting and video-recording as methods of measuring the duration of knee-straining work postures, and to evaluate the reproducibility of timings of the video-recordings. Thirty-nine carpenters and 33 floorlayers were video-filmed while working, and were asked immediately afterwards to quantify the amount of time spent in knee-straining positions. The investigators recorded the periods of knee-straining work with a stopwatch during playback of the video-film, and the agreement between the two investigators' measurements was studied in 13 pairs of measurements. The video-observation method was very effective for timing knee-strain work. Furthermore, Spearman's correlation coefficient (0.88) indicated a good association between observed and self-reported knee-straining work. Estimation of self-reported knee-straining work collected by interview showed good correlation with measurements of video-recordings. When judging the repeatability of timings of knee-straining work from the video-recordings, a high level of agreement was seen between the two observers in the 13 dual measurements of time spent in knee-straining work positions.
authors.affiliation: Clinic of Occupational Medicine, Glostrup Hospital, Denmark. SSAMALKJ@vibamt.dk
authors.forename: L K
authors.initials: LK
authors.lastname: Jensen
authors.forename: W
authors.initials: W
authors.lastname: Eenberg
authors.forename: S
authors.initials: S
authors.lastname: Mikkelsen
mesh_terms: D006801:Humans; D007718:Knee Injuries / Q000209:etiology*; D007719:Knee Joint / Q000502:physiology*; D016014:Linear Models; D009784:Occupational Diseases / Q000209:etiology*; D009790:Occupations; D011187:Posture; D015203:Reproducibility of Results; D013180:Sprains and Strains / Q000209:etiology*; D018709:Statistics, Nonparametric; D011795:Surveys and Questionnaires / Q000592:standards*; D013647:Task Performance and Analysis; D013997:Time Factors; D014743:Videotape Recording / Q000592:standards*; D014937:Work