Underutilization of meta-analysis in diagnostic pathology

Context.-No studies to our knowledge have investigated citations and utilization of meta-analysis in diagnostic pathology (DP). Objective.-To characterize meta-analyses in DP compared with meta-analyses in medicine. Design.-We searched PubMed for meta-analyses in 12 major DP journals without specifying years and in 4 major medicine journals in both 2006 and 2011. We compared articles' adjusted citation ratios (ACRs), defined as an article's citation count divided by the mean citations for the meta-analysis, review, and original research articles published in the same journal in the same year. Results.-Forty-one of 76 DP articles, 74 of 125 medicine articles in 2011, and 52 of 83 medicine articles in 2006 were qualified meta-analyses as identified by PubMed. The ACRs of DP meta-analysis articles were higher than those of original research articles (2.62 6 2.31 versus 0.92 6 0.84, P , .001) and similar to those of review articles in 2006 (2.62 6 2.31 versus 1.95 6 1.59, P = .50), but they were similar to both in 2011 (1.85 6 1.39 versus 0.99 6 1.43, P = .11; 1.85 6 1.39 versus 1.12 6 1.43, P = .21, respectively). Diagnostic pathology and medicine meta-analyses had similar ACRs (1.85 6 1.39 versus 1.57 6 1.35 in 2011, P = .60; and 2.62 6 2.31 versus 1.85 6 1.90 in 2006, P = .50, respectively). However, although DP journals published fewer metaanalyses (0.97% versus 6.66% in 2011 and 0.67% versus 4.40% in 2006, P , .001 for both), they published more meta-analyses using both original and published data than medicine (21.95% versus 1.59%, P , .001). They also published more meta-analyses per year in 2011-2014 than in 2000-2010 (6.4 6 1.29 versus 1.36 6 1.03 articles per year, P , .001). Conclusions.-We found underutilization of meta-analyses in DP, despite their high ACRs and recently increased utilization. More DP meta-analyses are needed.