Bias in assessment of nonverbal pain in compensation patients: does it exist?

This study examined whether providing information to rehabilitation professionals, on the compensation status of patients, would influence their rating of nonverbal expressions of pain. In an experimental design two groups of physiotherapists and occupational therapists were asked to view videotapes of 10 patients with shoulder pain undergoing a total of 88 pain induction tests. They were asked to rate the amount of pain the patients were experiencing based solely on the facial expression of pain. Bias was instilled in one group (n = 18) by informing them that the patients originated from a workers' compensation facility. Sixteen therapists served as a control group. Results indicate that the therapists rated the nonverbal expression of pain similarly regardless of their perceived compensation status. These findings suggest that the mistrust that is commonly experienced by patients on workers' compensation does not come from rehabilitation professionals but from other sources within the system. Alternative explanations for the findings and directions for future research are explored.