Data extraction We performed the data extraction using a standardized data extraction form, collecting information on the publication year, study design, number of cases, total sample size, population type, country, continent, mean age and clinical data. The event rate and confidence intervals (CI) were calculated. Statistical analysis Pooled event rate and 95% Inhibitors,research,lifescience,medical CI were calculated using a random effects model (24). We tested heterogeneity with Cochran’s Q statistic,
with P<0.10 indicating heterogeneity, and chemical structure quantified the degree of heterogeneity using the I2 statistic, which represents the percentage of the total variability across studies which is due to heterogeneity. I2 values of 25%, 50% and 75% corresponded to low, moderate and high degrees of heterogeneity
respectively (25). The quantified publication bias using the Egger’s regression model (26), with the effect of bias assessed using the fail-safe number method. The fail-safe number was the number of studies that we would need to have missed for our observed result to be nullified Inhibitors,research,lifescience,medical to statistical non-significance at the P<0.05 level. Publication bias is generally regarded as a concern if the fail-safe number is less than 5n+10, with n being the number of studies included in the meta-analysis (27). All analyses were performed with Comprehensive Meta-analysis Inhibitors,research,lifescience,medical (version 2.0). Results The original search strategy retrieved studies (Figure 1). The abstracts were reviewed and after applying the inclusion and exclusion criteria, articles were selected for full-text evaluation. Of the articles selected, only 20 met full criteria for analysis and are summarised in Table 1. The years of publication ranged from 2001 to 2013. Figure Inhibitors,research,lifescience,medical 1 Flow of included Inhibitors,research,lifescience,medical studies. Table 1 Characteristics of the studies included in the systematic review and meta-analysis The results of the three randomized controlled trials (RCTs) demonstrated that SEMS resulted in lower major [odds ratio (OR): 0.62, 95% CI: 0.021-18.371] and minor (OR: 0.32, 95% CI: 0.049-2.089) complications
in a shorter time to tolerating an oral intake (SEMS: 3.55 days and GJ: 7.15 days) and shorter hospital stay (SEMS: 5.1 days and GJ: 12.13 days). Among the non RCTs: SEMS resulted and in a shorter time to tolerating an oral intake (SEMS: 1.48 days and GJ: 8.07 days), lesser complications (OR: 0.33, 95% CI: 0.1-1.08), lower mortality (OR: 0.5, 95% CI: 0.21-1.20) and a shorter hospital stay (SEMS: 7.61 days and GJ: 19.04 days). There was no significant difference between median survival times among RCTs and non RCTs (Tables 2 and and33). Table 2 Pooled odd ratio and 95% CI of randomized trials and non-randomized trials Table 3 Outcomes of randomized trials and non-randomized trials Heterogeneity and publication bias No publication bias was detected using the Egger’s regression model.