Comparison of self-report, video observation and direct measurement methods for upper extremity musculoskeletal disorder physical risk factors

Abstract

The prevention of work-related musculoskeletal disorders has become a national priority in many countries. Increasingly, attempts are made to quantify those exposures that increase risk in order to set exposure limit values. This study used commonly employed field measurement methods and tools in order to perform an inter-method comparison between three primary methods of risk factor exposure assessment: self-report questionnaires, observational video analysis and direct measurement. Extreme posture duration, repetition, hand force (estimated from electromyography) and movement velocity were assessed for 18 subjects while performing each of three jobs processing tree seedlings. Results indicated that self-reports were the least precise assessment method, which consistently overestimated exposures for each of the measured risk factors. However, adjustment of the reports as psychophysical scales may increase agreement on a group level. Wrist flexion/extension duration and repetition were best measured by electrogoniometer. Electrogoniometric measures of wrist deviation duration and frequency were less precise than video analysis. Forearm rotation duration and repetition, grip force and velocity appeared to be best quantified by direct measurement as measured by electrogoniometer and electromyography (EMG) (as root-mean-square amplitude). The results highlight the fact that it is as important to consider and report estimated measurement error in order to reduce potential exposure misclassification in epidemiologic studies.

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).…”

Using Kinect™ sensor in observational methods for assessing postures at work

“…Unlike direct methods, observational methods have limitations in the sampling rates. Many studies have analyzed the degree of validity of the sampling rates and have compared their results with those of direct measurement methods; however these studies greatly differ in their conclusions (Alex Burdorf et al, 1992;Juul-Kristensen et al, 2001;Paquet et al, 2001;Spielholz et al, 2001).…”

Precision of measurements of physical workload during standardised manual handling. Part II: Inclinometry of head, upper back, neck and upper arms

“…By using technical measurements, which show a better validity, accuracy and precision than observation methods [17,29,36,37], the scientific basis of TLVs can be improved, and compliance surveyed.…”