Presentation M P16

M P16 (Poster Presentation):
Predictors of Workers' Compensation Claim Duration among Workers Disabled Due to Uncomplicated Low Back Pain

Presented by: Shanil Ebrahim


Busse JW1, Streenstra I2, Ebrahim S1, Heels-Ansdell D1, Walter SD1, Guyatt GH1

  1. McMaster University, Hamilton, Ontario
  2. Institute for Work & Health, Toronto, Ontario, Canada



Low back pain (LBP) is a common complaint among workers receiving Workers' Compensation wage replacement benefits. We used the administrative data from the Ontario Workplace Safety and Insurance Board (WSIB) to explore the association between baseline characteristics and commonly reimbursed therapies and time to claim closure among workers disabled due to LBP.


Using the WSIB administrative database, we acquired a random sample of 6,665 injured workers who reported an uncomplicated back injury (strain or sprain) with a date of injury between January 1, 2005 and June 30, 2005. We selected, a priori, 11 variables from the database that we judged may be associated with claim closure and predicted the direction of anticipated effects. We performed a time-to-event analysis using Cox proportional hazards regression to assess the association between time to claim closure and the independent variables. Receipt of WSIB-reimbursed chiropractic care or physiotherapy were treated as a time-dependent covariate to account for when treatment was initiated during the course of the disability claim.


Our adjusted regression analysis showed that older age and opioid prescription (adjusted hazard ratio [HR]=0.69; 99% CI=0.53, 0.89) in the first four weeks of claim reimbursed by the WSIB were associated with prolonged claim closure, whereas working for an employer that had a return-to-work program was associated with shorter claim duration (adjusted HR=1.73; 99%CI=1.42, 2.12). Neither reimbursement for chiropractic (adjusted HR=1.08; 99%CI=0.91, 1.29) or physiotherapy (adjusted HR=0.99; 99%CI=0.85, 1.16) were associated with time to claim closure.


Our analysis did not find support for use of chiropractic or physiotherapy services by Workers' Compensation LBP claimants. Our results do suggest that opioid prescription in the first four weeks of a WSIB claim is associated with delayed claim closure, and attachment to employers with return-to-work programs is associated with accelerated claim closure.

Schedule Details

Monday September 29
12:45 - 13:45 Poster Viewing
Session: Determinants of RTW