Validity of self-reported exposures to work postures and manual materials handling. Stockholm MUSIC I Study Group.

Abstract

were validated in relation to direct measurements and systematic observations on 39 men and 58 women representing 45 different occupation s. The agreement was tested at a dichotomous level and, when possible, with quantification of duration or frequency. At the dichotomous level the agreement was "acceptable" for nine variables concerning work postures and the handling of loads weighing >5 kg. No variable showed "accept able" agreement when the duration or the frequency was quantified in more detail (4-to 6-point scales). Musculoskeletal complaints seemed to introduce a differential bias for some lifting variables. Thus some variables for postures or the handling loads of > 5 kg may, under certain conditions, be acceptable for use in epidemiologic studies when the relative risks are high. However, self-rep orted exposure seems to be too crude if more-detailed information is required.

Self-administered questionnaire and direct observation by checklist: Comparing two methods for physical exposure surveillance in a highly repetitive tasks plant

“…However, the self-administered questionnaire seemed to be more accurate in identifying high risk workers in this setting of jobs with high physical demands. The poor agreement between self-administered and observational methods suggests that these methods may be complementary, and should be used in combination (Hagberg et al 1995;Li and Buckle 1999;Spielholz et al 2001;Leclerc 2005;Wiktorin et al 1993;Wiktorin et al 1999).…”

Lower Back Problems and Work-Related Risks in a South African Manganese Factory

“…Sensory threshold curves and perceived exertions have been shown to follow non-linear functions that require finer resolution in the lower and middle ranges [30]. The exposures at the higher end are quite rare, thus affecting the logistics of epidemiological validation studies [31]. Conditions that persist for more than half the work time may also be an obvious risk for the development of musculoskeletal disorders [32].…”

In musculoskeletal epidemiology are we asking the unanswerable in questionnaires on physical load?

“…The Scandinavian Journal of Work, Environment & Health has featured prominently in publications addressing the validity of self-reported physical load in epidemiologic research (3,4,5). These publications have taught us that well-designed questionnaires are able to identify relative differences in physical load among occupational groups and, hence, rank these groups as to their level of physical load.…”