The Patient-Specific Functional Scale: validity in workers' compensation claimants

Arch Phys Med Rehabil. 2008 Jul;89(7):1294-9. doi: 10.1016/j.apmr.2007.11.040. Epub 2008 Jun 13.


Objective: To examine the construct and predictive validity of the Patient-Specific Functional Scale (PSFS) in workers' compensation claimants.

Design: Prospective cohort study with 1-year follow-up.

Setting: A workers' compensation rehabilitation facility.

Participants: Subjects included 294 claimants with a variety of musculoskeletal disorders. The sample was predominantly male (70%), with a mean age of 44 years. Subjects completed a battery of measures at baseline including the PSFS, the Pain Disability Index (PDI), and the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36).

Interventions: Not applicable.

Main outcome measures: Outcomes for determining predictive validity included administrative indicators of timely return to work and recovery during the 1-year follow-up. Analysis included Pearson correlation and multivariable Cox and logistic regression.

Results: At baseline, the PSFS correlated moderately (r range, 0.3-0.5) with other indicators of functional limitation (PDI, SF-36 role-physical subscale) but negligibly with the SF-36 mental health and role-emotional subscales. The PSFS was associated with timely recovery (adjusted hazard ratio, 1.16; 95% confidence interval, 1.07-1.27) with increasing functional limitation related to delayed recovery.

Conclusions: Results provide construct and predictive validity evidence for the PSFS as an indicator of functional limitation in workers' compensation claimants.

Publication types

  • Research Support, Non-U.S. Gov't
  • Validation Study

MeSH terms

  • Adult
  • Female
  • Health Status Indicators*
  • Humans
  • Male
  • Middle Aged
  • Musculoskeletal Diseases / rehabilitation*
  • Outcome Assessment, Health Care
  • Pain Measurement
  • Predictive Value of Tests
  • Prospective Studies
  • United States
  • Workers' Compensation*