BACKGROUND: This is the first systematic review and meta-analysis of the large body of data describing the Swedish adjustable gastric band (SAGB) and Lap-Band (LB). METHODS: A systematic review was performed that included screening of studies published in any language (January 1, 1998 through April 30, 2006) identified through MEDLINE, Current Contents, or the Cochrane Library. Studies with > or =10 SAGB or LB patients reporting > or =30-day efficacy or safety outcomes were eligible for review; the data were extracted from the accepted studies. A weighted means analysis and random-effects meta-analysis of efficacy outcomes of interest were conducted. RESULTS: A total of 4592 bariatric surgery studies met the initial criteria. Of these studies, 129 (28,980 patients) were accepted (33 SAGB and 104 LB studies); most had a retrospective single-center design. For 4273 patients (36 treatment groups) in 33 SAGB studies and 24,707 patients (111 groups) in 104 LB studies, the mean baseline age (39.1-40.2 yr), body mass index (43.8-45.3 kg/m2), and gender (women 79.2-82.5%) were similar. A laparoscopic technique was used in > or =88% and a pars flaccida technique in > or =41% of both groups. Early mortality was equivalent for SAGB/LB (