Does knowledge of a patient's workers' compensation status influence clinical judgments?

It is generally acknowledged that compensation payments (WCB) influence rehabilitation outcome in a negative manner. Patients receiving WCB have more treatment over a longer time period than their non compensated (NWCB) cohorts. It is not clear whether therapists (PT) perceive WCB clients as being more impaired and expect them to have a worse outcome than clients without WCB. The purpose of this study was to determine whether PTs' clinical judgments are influenced by the knowledge of a patients WCB status and whether this knowledge influences their assessment findings or prognostic judgments. A convenience sample of 69 physical therapists (PTs) participated. Each PT viewed three videotaped assessments, of patients with low back pain (LBP) that differed in severity. The PT was provided with a brief history of the patient. Included in the history was a statement that the patient was (WCB group), or was not (NWCB group) in receipt of workers compensation benefits (WCB). The third group of PTs was given no information (control group) about the patient. PTs recorded physical assessment findings and made prognostic judgments about the patients. Data for the physical assessment findings and prognoses recorded by the PTs was analyzed across information groups using ANOVA. Knowledge of compensation status did not influence the PTs' physical assessment findings but did influence prognostic judgments. WCB status was deemed to have a negative effect on outcome in patients with mild LBP. Additionally, NWCB status was deemed to have a positive influence on outcome in patients with severe LBP. The differences were most marked in the short term (1 month). It was concluded that PTs expectations of outcome are influenced by prior knowledge of compensation status.