Meta-Analyses of Randomized Controlled Trials

TLDR

Meta‑analysis is a method that aggregates and evaluates findings from prior studies. The authors assessed 86 meta‑analyses using a 23‑item scoring system covering study design, combinability, bias control, statistical analysis, sensitivity analysis, and result application. Among 86 meta‑analyses of randomized controlled trials, only 28 % fully addressed all six quality domains, with most studies covering fewer areas, highlighting a critical need for better methods in literature searching, trial quality assessment, and synthesis. Citation: N Engl J Med 1987; 316:450–5.

Abstract

Abstract A new type of research, termed meta-analysis, attempts to analyze and combine the results of previous reports. We found 86 meta-analyses of reports of randomized controlled trials in the English-language literature. We evaluated the quality of these meta-analyses, using a scoring method that considered 23 items in six major areas — study design, combinability, control of bias, statistical analysis, sensitivity analysis, and application of results. Only 24 meta-analyses (28 percent) addressed all six areas, 31 (36 percent) addressed five, 25 (29 percent) addressed four, 5 (6 percent) addressed three, and 1 (1 percent) addressed two. Of the 23 individual items, between 1 and 14 were addressed satisfactorily (mean ±SD, 7.7±2.7). We conclude that an urgent need exists for improved methods in literature searching, quality evaluation of trials, and synthesizing of the results. (N Engl J Med 1987; 316:450–5.)