Overviews are methodically inferior to systematic reviews and contribute to myths of effective drugs

In a recent overview encompassing systematic reviews and randomized trials of pharmacotherapy in low back pain (LBP), the authors concluded that there is good evidence that acetaminophen, NSAID and muscle relaxants provide moderate pain relief in acute LBP (1). In another clinical guideline article in the same issue of the Annals (2), the recommended indications for acetaminophen and NSAIDs are extended to include chronic LBP, whereas tramadol, opiods, and benzodiazepines are recommended both in acute and chronic LBP despite the lack of “good” or even “fair” evidence. The methodology used by the authors to review the literature may be flawed in the sense that it merely reiterates what other reviewers have published previously. The current overview does not address crucial differences in focus and protocols of the included reviews, and fails to adequately assess the randomized controlled trials which are the primary sources for information. The criteria list which was used does not i...