P05.11
Purpose: Determining efficacy and controlling for non-specific effects in complementary and alternative medicine (CAM) require valid placebo or sham control groups that generate similar levels of expectancy, credibility and therapist attention and ensure successful patient blinding. To differentiate specific effects of Craniosacral Therapy (CST) from non-specific, placebo-related mechanisms a new sham-control procedure was developed and tested for its credibility.
Methods: Patients from a randomized controlled trial on chronic neck pain (NCT01526447) completed the Credibility/Expectancy Questionnaire and the Helping Alliance Questionnaire as well as questions about compliance and safety. Patients in the treatment group received 8 individual CST sessions once a week whereas sham group patients received light touch of the same extent. Complete (N=50) and multiple imputed data (N=54) were analyzed separately using a logistic regression model with patients' ratings as independent predictors and group assignment as dependent variable. An additional t-test for analysis of the overall compliance/attendance was computed.
Results: Patients' ratings of treatment expectancy, treatment credibility and therapeutic alliance were not found to have a significant power for classifying cases into CST or sham group (p ≥ .05). Only satisfaction with treatment revealed a significant adjusted odds ratio (AOR: 6.83; 95% CI: [1.54; 30.24]; p=.011) in the analysis of the complete cases, but was not stable for the imputed dataset (AOR: 4.09; 95% CI: [0.94; 17.76]; p=.060). Compliance of both groups was comparable (p=.054) as were reasons for non-attendance. No serious adverse events were reported.
Conclusion: Study results indicate that blinding patients to treatment allocation was successful; patients' expectancy, credibility and alliance to the therapist did not appear to affect study outcomes, and sham manipulation was tolerable and safe. The design can therefore be regarded as a credible means to control for placebo effects in future CST clinical trials.
Contact: Heidemarie Haller, h.haller@kliniken-essen-mitte.de
