JAMA : the journal of the American Medical Association
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Review Meta Analysis Comparative Study
Stopping randomized trials early for benefit and estimation of treatment effects: systematic review and meta-regression analysis.
Theory and simulation suggest that randomized controlled trials (RCTs) stopped early for benefit (truncated RCTs) systematically overestimate treatment effects for the outcome that precipitated early stopping. ⋯ Truncated RCTs were associated with greater effect sizes than RCTs not stopped early. This difference was independent of the presence of statistical stopping rules and was greatest in smaller studies.
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Review Meta Analysis
Vitamin B6 and risk of colorectal cancer: a meta-analysis of prospective studies.
Mounting evidence indicates that vitamin B(6), a coenzyme involved in nearly 100 enzymatic reactions, may reduce the risk of colorectal cancer. ⋯ Vitamin B(6) intake and blood PLP levels were inversely associated with the risk of colorectal cancer in this meta-analysis.
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Review Meta Analysis
Higher vs lower positive end-expiratory pressure in patients with acute lung injury and acute respiratory distress syndrome: systematic review and meta-analysis.
Trials comparing higher vs lower levels of positive end-expiratory pressure (PEEP) in adults with acute lung injury or acute respiratory distress syndrome (ARDS) have been underpowered to detect small but potentially important effects on mortality or to explore subgroup differences. ⋯ Treatment with higher vs lower levels of PEEP was not associated with improved hospital survival. However, higher levels were associated with improved survival among the subgroup of patients with ARDS.