Beyond Return to Work: Testing a Measure of at-work Disability in Workers with Musculoskeletal Pain

AbstractBackground: There are a limited number of validated measures of a patient’s perception of the level of difficulty that they are having at their job. The purpose of this study was to evaluate the psychometric properties of the 16-item Work Limitations Questionnaire (WLQ-16). Methods: A sample of 42 workers reporting to a workplace occupational health unit with upper limb or low back pain were enrolled in an observational study. Participants were assessed at baseline, 4 and 12 weeks post reporting. Psychometric testing (distributions, Cronbach’s alpha, construct validity and responsiveness to change in problem and pain) was done using the baseline and 12-week data. Results: The WLQ-16 had evidence of internal consistency, construct validity and responsiveness. Some ceiling effect was found in the domains of mental-interpersonal and output demands. Physical demands suffered from missing values in 18/42 due to not-applicable content. Construct validity revealed that there was less discrimination at the higher (less limited) end of the scale. Responsiveness was present, though less than found with other measures of function and pain. Conclusions: The WLQ-16 shows promise as a measure of at-work disability. Further testing to evaluate the ceiling effect and responsiveness to constructs of change more closely related to work disability is recommended.

[1]  J. Jacobs,et al.  Overview of work disability in rheumatoid arthritis patients as observed in cross-sectional and longitudinal surveys. , 2004, Arthritis and rheumatism.

[2]  C. Bombardier,et al.  Describing the Burden of Upper-Extremity Musculoskeletal Disorders in Newspaper Workers: What Difference do Case Definitions Make? , 2000, Journal of Occupational Rehabilitation.

[3]  Benjamin C Amick,et al.  Predictors of Successful Work Role Functioning After Carpal Tunnel Release Surgery , 2004, Journal of occupational and environmental medicine.

[4]  M. Roland,et al.  A study of the natural history of back pain. Part I: development of a reliable and sensitive measure of disability in low-back pain. , 1983, Spine.

[5]  J. David Cassidy,et al.  A Systematic Review of the Prognosis of Acute Whiplash and a New Conceptual Framework to Synthesize the Literature , 2001, Spine.

[6]  S. Hogg-Johnson,et al.  The association between neck pain intensity, physical functioning, depressive symptomatology and time-to-claim-closure after whiplash. , 2001, Journal of clinical epidemiology.

[7]  P. Stratford,et al.  Defining the minimum level of detectable change for the Roland-Morris questionnaire. , 1996, Physical therapy.

[8]  B C Amick,et al.  A review of health-related work outcome measures and their uses, and recommended measures. , 2000, Spine.

[9]  W. Stewart,et al.  Health-Related Lost Productive Time (LPT): Recall Interval and Bias in LPT Estimates , 2004, Journal of occupational and environmental medicine.

[10]  Aileen M. Davis,et al.  The DASH (Disabilities of the Arm, Shoulder and Hand) Outcome Measure: What do we know about it now? , 2001 .

[11]  Ernst R Berndt,et al.  Relationship of Employee-Reported Work Limitations to Work Productivity , 2003, Medical care.

[12]  L. Pizzi,et al.  Health-Related Workplace Productivity Measurement: General and Migraine-Specific Recommendations from the ACOEM Expert Panel , 2003, Journal of occupational and environmental medicine.

[13]  C. Bombardier,et al.  Measuring the whole or the parts? Validity, reliability, and responsiveness of the Disabilities of the Arm, Shoulder and Hand outcome measure in different regions of the upper extremity. , 2001, Journal of hand therapy : official journal of the American Society of Hand Therapists.

[14]  Paul E. Stang,et al.  Using the World Health Organization Health and Work Performance Questionnaire (HPQ) to Evaluate the Indirect Workplace Costs of Illness , 2004, Journal of occupational and environmental medicine.

[15]  Jacqui Smith,et al.  Development of a work instability scale for rheumatoid arthritis. , 2003, Arthritis and rheumatism.

[16]  M. Liang,et al.  Comparative Measurement Sensitivity of Short and Longer Health Status Instruments , 1992, Medical care.

[17]  R A Deyo,et al.  Outcome Measures for Low Back Pain Research: A Proposal for Standardized Use , 1998, Spine.

[18]  P. Brandt-Rauf,et al.  Measuring and evaluating the effects of disease on workplace productivity. , 2004, Journal of occupational and environmental medicine.

[19]  J. Wright,et al.  A comparison of different indices of responsiveness. , 1997, Journal of clinical epidemiology.

[20]  S. Sullivan.  Making the Business Case for Health and Productivity Management , 2004, Journal of occupational and environmental medicine.

[21]  C. Bombardier,et al.  Minimal clinically important difference. Low back pain: outcome measures. , 2001, The Journal of rheumatology.

[22]  R. Epstein,et al.  Interpretation of quality of life changes , 1993, Quality of Life Research.

[23]  James G Wright,et al.  Development of the QuickDASH: comparison of three item-reduction approaches. , 2005, The Journal of bone and joint surgery. American volume.

[24]  K. Bungay,et al.  The Work Limitations Questionnaire , 2001, Medical care.

[25]  W. Spitzer,et al.  Scientific monograph of the Quebec Task Force on Whiplash-Associated Disorders: redefining "whiplash" and its management. , 1995, Spine.

[26]  E. Berndt,et al.  The Clinical and Occupational Correlates of Work Productivity Loss Among Employed Patients With Depression , 2004, Journal of occupational and environmental medicine.

[27]  L. D. de Witte,et al.  Assessing the responsiveness of a functional status measure: the Sickness Impact Profile versus the SIP68. , 1997, Journal of clinical epidemiology.

[28]  Danny R. Miller,et al.  AND ITS MANAGEMENT , 1973 .

[29]  K. Lorig,et al.  Development and evaluation of a scale to measure perceived self-efficacy in people with arthritis. , 1989, Arthritis and rheumatism.

[30]  R A Deyo,et al.  Assessing the responsiveness of functional scales to clinical change: an analogy to diagnostic test performance. , 1986, Journal of chronic diseases.

[31]  R. Devellis.  A consumer's guide to finding, evaluating, and reporting on measurement instruments. , 1996, Arthritis care and research : the official journal of the Arthritis Health Professions Association.

[32]  C. McHorney,et al.  Individual-patient monitoring in clinical practice: are available health status surveys adequate? , 1995, Quality of Life Research.

[33]  Scientific approach to the assessment and management of activity-related spinal disorders. A monograph for clinicians. Report of the Quebec Task Force on Spinal Disorders. , 1987, Spine.

[34]  C. Bombardier,et al.  A taxonomy for responsiveness. , 2001, Journal of clinical epidemiology.

[35]  M. Roland,et al.  The Roland-Morris Disability Questionnaire and the Oswestry Disability Questionnaire. , 2000, Spine.

[36]  R. Deyo,et al.  The significance of treatment effects: the clinical perspective. , 1995, Medical care.

[37]  L I Boden,et al.  Social and economic impacts of workplace illness and injury: current and future directions for research. , 2001, American journal of industrial medicine.

[38]  Jacob Cohen.  Statistical Power Analysis for the Behavioral Sciences , 1969, The SAGE Encyclopedia of Research Design.