Specification of Interventions and Selection of Control in Acupuncture Randomized Controlled Trials: A Cross-Sectional Study

Background: Specification of interventions and selection of control are two methodological determinants for a successful acupuncture trial. However, it is not fully understood about the current practice of these two determinants. We thus conduced a cross-sectional study to examine specification of interventions and selection of control among current acupuncture randomized controlled trials (RCTs). Methods: We searched PubMed for acupuncture RCTs published in the core clinical journals and complementary and alternative medicine (CAM) journals from January 2010 to December 2019 (10 years), and included RCTs that assessed treatment effects of acupuncture versus any type of control. Teams of methods-trained investigators who had experiences in acupuncture trials independently screened reports for eligibility and collected data, using a prespecified standardized questionnaire. We used network meta-analyses to investigate whether treatment effect was differential in patients with chronic pain when using sham acupuncture as a control versus using waiting-list or no treatment.Results: Of 319 eligible RCTs, most well specified style of acupuncture (86.8%), acupoint prescription (96.2%), type of needle stimulation (90.3%) and needle retention time (85.6%). However, other acupuncture details were less specified, including achievement of response sought (65.5%) and needle manipulation (50.5%), specification of number of needle insertions (21.9%), angle and direction of insertion (31.3%), patients posture (32.3%) and co-interventions (22.9%). Sham acupuncture (41.4%) was the most frequently used control, followed by waiting-list or no treatment (32.9%). There was no differential treatment effect when using sham acupuncture versus waiting-list/no treatment as a control (SMD = -0.15, 95% CI -0.91 to 0.62).Conclusions: Over a decade of research practice, important gaps remained in the specification of acupuncture interventions, including specification of response sought, needle manipulation, and co-interventions. While sham acupuncture was largely used, waiting-list or no treatment may also be used as an appropriate control.