Meta-analysis is a systematic and objective methodology for synthesizi
ng research literature. The authors present the history and definition
of meta-analysis, discuss the generic framework for design and implem
entation of a meta-analysis, and review the problems and pitfalls that
can accompany meta-analyses. Their discussion draws on practical expe
rience with several meta-analyses of the low back pain literature. Met
a-analysis can be used to help answer the questions about various opti
ons for diagnosis and treatment of low back problems and also to point
out gaps in our knowledge base that may have a high priority for rese
arch. Meta-analytic methods are an informative means of addressing hea
lth care controversies with major patient management and cost implicat
ions.