An analysis of review articles and controlled clinical trials for temporomandibular disorders and similar chronic musculoskeletal pain disorders was carried out. Although little evidence was found that any specific therapy had long-term efficacy greater than placebo, we did find strong evidence that symptoms improve during treatment with ost forms of physical therapy, including placebo. When the frequency of significant between-group differences in trials that used placebo and waiting list control (i.e., no treatment) groups were compared, it was found that treatment was better than placebo in only 7/22 trials, whereas treatment was almost always better than no treatment (15/16). This difference was highly significant (P=0.001). A similar analysis of trials that included more than one treatment group showed that while equal amounts of treatment were usually associated with equal outcome (9/10), unequal treatment regimes led to unequal outcome (10/15; P=0.012). The group that received the most therapy appeared to do best. In conclusion, it seems that patients are helped during the period that they are being treated with most forms of physical therapy. However, most of these therapies have not been shown to be more efficacious than placebo.
aFaculty of Dentistry, McGill University, Montreal, Quebec, Canada
bDepartment of Epidemiology and Biostatistics, Faculty of Medicine, McGill University, Montreal, Quebec, Canada
cDepartment of Physiology, Faculty of Medicine, McGill University, Montreal, Quebec, Canada
dCentre de Recherche en Sciences Neurologiques, Université de Montréal, Montréal, Quebec, Canada
*Corresponding author. Faculty of Dentistry, McGill University, 3640 University Street, Montreal, Quebec H3A 2B2, Canada. Tel.: +1 514 398 7203 (7223); fax: +1 514 3988900; e-mail: email@example.com
Received August 10, 1996; revised version received October 21, 1996; accepted October 28, 1996.