Wen-Lin Lee

Is Acupuncture Analgesia an Expectancy Effect? Preliminary Evidence Based on Participants’ Perceived Assignments in Two Placebo-Controlled Trials

This purpose of this article is to contrast the analgesic efficacy of acupuncture following dental surgery with the analgesic effects based on the expectation of benefit in two independently conducted placebo-controlled trials evaluating acupuncture as an adjunctive therapy for dental surgery. Both trials used pain following dental surgery as the outcome variable, and both included a blinding check to ascertain patients’ beliefs regarding which treatment they were receiving. Although no statistically significant analgesic effect was observed between the acupuncture and placebo groups, participants in both experiments who believed they received real acupuncture reported significantly less pain than patients who believed that they received a placebo. Patients’ beliefs regarding the receipt of acupuncture bore a stronger relationship to pain than any specific action possessed by acupuncture. These results also support the importance of both employing credible controls for the placebo effect in clinical trials and evaluating the credibility of those controls.

The Growth of Health-Related Meta-Analyses Published from 1980 to 2000

A MEDLINE search was conducted to estimate trends in the growth of health-related meta-analyses published during the past two decades. Employing a more specific than sensitive search strategy, and not supplementing these results with known sources of published meta-analyses or manual search strategies, 3,025 probable meta-analyses were selected from the 5,128 citations identified. The data showed a definitive upward (and generally linear) trend across time with no evidence for this genre of research either leveling off or decreasing.