The validation of an active control intervention for Mindfulness Based Stress Reduction (MBSR)

Abstract

Most of the extant literature investigating the health effects of mindfulness interventions relies on wait-list control comparisons. The current article specifies and validates an active control condition, the Health Enhancement Program (HEP), thus providing the foundation necessary for rigorous investigations of the relative efficacy of Mindfulness Based Stress Reduction (MBSR) and for testing mindfulness as an active ingredient. 63 participants were randomized to either MBSR (n = 31) or HEP (n = 32). Compared to HEP, MBSR led to reductions in thermal pain ratings in the mindfulness- but not the HEP-related instruction condition (η(2) = .18). There were significant improvements over time for general distress (η(2) = .09), anxiety (η(2) = .08), hostility (η(2) = .07), and medical symptoms (η(2) = .14), but no effects of intervention. Practice was not related to change. HEP is an active control condition for MBSR while remaining inert to mindfulness. These claims are supported by results from a pain task. Participant-reported outcomes (PROs) replicate previous improvements to well-being in MBSR, but indicate that MBSR is no more effective than a rigorous active control in improving these indices. These results emphasize the importance of using an active control condition like HEP in studies evaluating the effectiveness of MBSR.

Conflict of interest statement

No author had any conflict of interest unless specified above.

Copyright © 2011 Elsevier Ltd. All rights reserved.

Figures

Figure 1

CONSORT diagram detailing retention rates by study phase and reasons for dropouts.

Figure 2

(a) Method details for pain task trials, including Likert scales rating Intensity (Int) and Unpleasantness (Unp) of thermal stimuli. (b) Intervention × Time interaction for averaged pain intensity and pain unpleasantness ratings of hot stimuli for the Control instruction condition subtracted from the Mindfulness instruction condition.

Figure 3

(a) Intervention × Time interaction for the SCL-90-R GSI scale. Error bars represent one standard error above and below the mean. (b) Intervention × Time interaction for the SCL-90-R Depression sub-scale.