"Playing their parts": the experiences of participants in a randomized sham-controlled acupuncture trial

Qualitative research has an important part to play in investigating how complex interventions are implemented within randomized controlled trials (RCTs) and what impact the RCT context has on participants, their behavior, and their outcomes. We explored these issues within a randomized sham-acupuncture controlled trial of traditional Chinese acupuncture for people with migraine.

All trial participants who consented to take part in this qualitative study were interviewed twice by a researcher who was blind to all trial data. The acupuncture practitioner was interviewed once. Nineteen (19) semistructured interviews, 30-60 minutes long, were transcribed, coded, and analyzed both across and within cases.

The 10 participants, 6 female, age 23-70 years had severe migraine and conventional treatment had been of limited benefit. They were satisfied with the organization of the trial and no acupuncture was perceived as obviously "sham." Most participants, and the practitioner, actively "played their part" in the trial, taking on research roles that differed from their usual roles of "patient" and "doctor." The resulting changes to their normal expectations and behavior influenced how the intervention was delivered and experienced. There was a reduction in talking, explanations, and participation, and treatment was focused on the migraine and usually excluded other conditions, even if the participants considered them to be a cause or a trigger of the migraine.

We conclude that treatment in the trial differed from that described in studies of "real life" traditional acupuncture. These differences affected the needling-the characteristic or specific intervention-as well as contextual factors. This trial design limitation appears to be inevitable when a sham-controlled design is used to research an intervention that is based on a holistic and participative treatment strategy. These findings should be taken into account in the design and interpretation of RCTs of complex interventions such as acupuncture.