Letters Section Editor: Robert M. Golub,
MD, Senior Editor.
To the Editor: We are concerned that the systematic
review and meta-analysis of bariatric surgery by Dr Buchwald and colleagues1 did not describe the quality of the included studies.
A formal assessment of data quality, even after study selection is complete,
is a critical step in conducting a systematic review.2- 4 In
this review, study quality was considered only through the use of inclusion
criteria. These particular criteria did not ensure that the included studies
were of high quality. For example, some of the included studies were retrospective,
some may have used self-reported weights, and some analyzed only a subset
of the total population of patients who received surgery and may have differed
in important ways from the full population of enrolled patients. These quality
concerns mean that, although patients lost weight after surgery, caution is
required when interpreting the meta-analytic point estimates. Also at issue
is that combined data were from many different postsurgical time points (eg,
6 months, 2 years, 5 years), and this approach may not accurately portray
the amount of weight loss at any given time.
Treadwell JR, Turkelson CM. Systematic Review of Bariatric Surgery. JAMA. 2005;293(14):1726. doi:10.1001/jama.293.14.1726-a