Meta-analysis in otolaryngology.
OBJECTIVE
To examine the results of meta-analyses in otolaryngology and compare these results with the individual component studies that constitute each meta-analysis.


METHODS
A retrospective review of the literature.


METHODS
Studies that conducted pooled statistical systematic analyses indexed on MEDLINE for the 10-year period from January 1989 to January 1999 were selected for keyword or subject headings of meta-analysis and otolaryngology (N = 22). Analysis consisted of a modified funnel graph depiction of the individual studies that made up each meta-analysis. Each meta-analysis was evaluated for consistency among these individual studies and comparison of the median result with the weighted mean meta-analysis result. In addition, the methodologic quality of each meta-analysis was assessed in terms of the rigor with which component studies were evaluated.


RESULTS
Ten (46%) of the 22 meta-analyses did not provide the individual study results that made up their meta-analyses. The results of 10 studies (46%) were similar to the median result of their individual component studies. The results of 2 studies (9%) differed from this median result, with widely heterogeneous component study results.


CONCLUSIONS
A large proportion of meta-analyses in otolaryngology (46%) fail to provide the individual study results necessary to analyze the meta-analysis result critically. Most remaining studies do provide results that accurately compare with the median of their component study results. Only a small proportion of meta-analyses were found to have disparate results, and each appropriately discusses the heterogeneity of the individual studies that comprise their meta-analysis.
Alsarraf
R
R
Department of Otolaryngology-Head and Neck Surgery, University of Washington School of Medicine, Seattle 98195, USA. amro@u.washington.edu
Alsarraf
N W
NW
Kato
B M
BM
Goldman
N D
ND
D005069:Evaluation Studies as Topic; D006801:Humans; D015201:Meta-Analysis as Topic; D010036:Otolaryngology; D012189:Retrospective Studies