Does the use of a prescriptive clinical prediction rule increase the likelihood of applying inappropriate treatments? A survey using clinical vignettes.

Clinical prediction rules (CPR) have been promoted as a natural progression in treatment decision-making. Methodological limitations of derivation and validation studies have resulted in some researchers questioning the indiscriminate use of CPRs. The purpose of this study was to explore the influence of the lumbar spine manipulation CPR (LCPR) use on clinical decision making through a survey of practicing clinicians. A sample of 535 physiotherapists from the United States, who routinely use thrust manipulation (TM), agreed to participate in this study. Those who use and those who do not use the LCPR determined group designation. A 9-step clinical vignette progressed a fictitious patient meeting the LCPR from no medical concern to significant concern for general health. A 2 × 9 chi-square was used to analyze the progression of decision-making. APTA board certification (P = 0.04), gender (P < 0.01), and manual therapy course attendance (P = 0.04) may increase and following the McKenzie philosophy (P < 0.01) may decrease the use of the LCPR. Subjects using the LCPR were more likely to choose to manipulate the patient (P < 0.01 and P = 0.02) during the first 2 scenarios of the vignette but both groups avoided TM equally as the medical concerns progressed. The results would suggest that subjects who routinely use TM would modify their decision-making to accommodate medical complications that preclude the indication for TM, and hence a potentially harmful intervention. This propensity to modify behaviour, was seen in both groups, regardless of their initial tendency to use the LCPR.