Table 2

Methodology of meta-analysis

Protocol development
     Definition of population, intervention and outcomes
     Specification of data sources and selection criteria
Search strategy
     Adequate comprehensiveness
     Sources and techniques
     Language restrictions
Study selection
     A priori criteria
     Justification of exclusions
Methodologic quality assessment
     Basis for inclusion, explanation of heterogeneity or sensitivity
          analyses
     Minimization of bias
     Quality scoring system
Data extraction
     Specification of data to be extracted
     Avoidance of bias
     Inclusion of all relevant data
Analysis
     Appropriate model (fixed versus random effects)
     Effect size (eg relative risk, odds ratio, risk difference)
     Precision (confidence intervals)
     Evaluation of heterogeneity
     Subgroup analyses
     Sensitivity analyses

Sibbald Critical Care 2000 4(Suppl 2):S8   doi:10.1186/cc970