COPAHS Study: protocol of a randomised experimental study comparing the effects of hypnosis, mindfulness meditation, and spiritual practices on experimental pain in healthy adults

BACKGROUND: There has been an increasing interest in studying the potential benefits of so-called complementary and alternative approaches for pain management, such as hypnosis and mindfulness-based interventions. More recently, researchers have been interested in studying the effects of spiritual practices on pain experience as well. These practices may increase pain tolerance, result in a positive re-appraisal of pain and influence other psychological variables that are known to be associated with pain experience. The purpose of this study is to evaluate and compare the immediate effects of self-hypnosis, mindfulness meditation, and a spiritual intervention relative to a control condition for increasing pain tolerance and reducing pain intensity and pain-related stress, in response to experimental painful stimulation. METHODS AND ANALYSIS: Recruitment is anticipated to start in November 2020. This is a randomised quantitative experimental mixed-design repeated-measures study with three assessment points: baseline (T0), pre-test (T1) and post-test (T2). Eligible healthy adults will be randomised to one of the four study conditions. Interventions will be a 20-minute audio-guided practice of either self-hypnosis, mindfulness meditation, or Christian prayer. Participants in the control group will not be instructed to use any specific strategy during the painful stimulation. Participants will be submitted to a first cycle of Cold Pressor Arm Wrap. They will then listen to a 20-minute audio recording inducing one of the three interventions, or, in the case of the control group, to a 20-minute audio recording of text from a natural history textbook. Primary outcomes are pain intensity and pain tolerance. Pain-related stress as measured by salivary cortisol level and heart rate variability are secondary outcomes. ETHICS AND DISSEMINATION: This study was approved by ISPA—University Institute’s internal Ethics Committee for Research on 3rd December 2018 (reference I/010/12/2018). Findings will be published in peer-reviewed indexed journals and presented at conferences. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov registry (NCT04491630). Stage: pre-results.