Responses to a systematic review

Article type
Authors
Herbison P, Hay-Smith J
Abstract
Background: The systematic review comparing the use of anticholinergic drugs for over active bladder with placebo was not received well in some circles. [1,2] The review concluded that drugs produced small, statistically significant, improvements over placebo, but it was not clear whether they were any use in real life.

Objectives: Because of negative, but non-specific, comments on the review it was decided to investigate the written responses to the review.

Methods: The ISI Web of Science and Google Scholar were searched for citations of the systematic review on the 22nd February 2005. The journal web site was consulted for responses to the paper. The articles citing the review or the paper were retrieved in full. Two investigators independently read the articles, and carried out a content analysis.
Results: Thirty-one of thirty-three articles were retrieved. Six main types of response were noted:

To support a statement about the effect of anticholinergic drugs.

To support some other statement about anticholinergic drugs.

To support the design of further research.

To criticise some aspect of the review.

To notify that the review had been seen.

To mention of some of the findings.
Only one article and two of the letters offered constructive criticism.

Conclusion: The general impression that this review was not well received is not really confirmed in the articles that cited it. Most citations did not make it clear whether they approved of the review or not. The next most common was to imply the review was wrong but give no reason. Only three tried to argue whether the conclusions were scientifically justified. Verbal comments in less formal situations had harsher criticisms than if they were written. Several of the citations confused efficacy and effectiveness, using them as if they were synonyms. No one has made use of the comments and criticisms feature of the Cochrane Library.
1. Anticholinergic drugs versus placebo for overactive bladder syndrome in adults. Cochrane Library. Issue 3. Oxford: Update Software, 2002.
2. Effectiveness of anticholinergic drugs compared with placebo in the treatment of overactive bladder: systematic review. BMJ 2003;726:841-4.