{smcl} {* *! version 2.01 01jan2022}{...} {viewerdialog maanova "dialog maanova"}{...} {marker syntax}{...} {title:Syntax} {phang} Subgroup (categorica) fixed- and random-effects inverse-variance weighted meta-analysis. {p 8 16 2} {cmd:maanova} {effectsizevar} {catvar} {ifin} {cmd:,} {opt var(varname)} {opt w(varname)} {opt se(varname)} [_options_] {pstd} where {it:effectsize} is the effect size variable and {it:catvar} is a categorical variable. The {it:effect size} can be any effect size type, such as Cohen's {it:d}, Hedges' {it:g}, logged odds ratio, logged risk ratio, logged logit, {it:r} or Fisher's {it:Zr}, among others. It is critical that the effect size is in its analyzable form. For example, the effect size can be a logged odds ratio but not an odds ratio. One of the following must also be specified: {phang2} o {it:var({varname})}: the variance of the effect size {phang2} o {it:w({varname})}: the inverse variance weight of the effect size {phang2} o {it:se({varname})}: the standard error of the effect size {pstd} The relationship among these is assumed to be {it:w} = 1/{it:var} = 1/{it:se^2}. {p_end} {marker reoptions}{...} {synoptset 20 tabbed}{...} {synopthdr :Options} {synoptline} {syntab:Model Type} {synopt :{opt model(_string_)}} model type; default is REML (restricted maximum likelihood); options include FE (fixed effect), DL (Dersimonian & Laird), HE (Hedges'), HS (Hunter & Schmidt), SJ (Sidik-Jonkman), SJIT (Sidik-Jonkman, iterative), ML (maximum likelihood), REML (restricted maximum likelihood), and EB (empirical bayes) {p_end} {syntab:Print Options} {synopt :{opt print(_string_)}} print options convert results for ease of interpretation; {it:exp} exponentiates results, {it:ivzr} is the inverse Fisher's {it:z} transformation, producing {it:r}, and {it:prop} converts logits back into proportions {p_end} {syntab:Tau^2 Options} {synopt :{opt tau_unique(_string_)}} specifies whether a common (default) or subgroup specific tau^2 is used. {it:tau_unique(YES)} will estimate a separate tau^2 for each subgroup. {p_end} {marker description}{...} {title:Description} {pstd} {cmd:maanova} performs a subgroup or categorical moderator meta-analysis under either a fixed-effect model (also called a common-effect model) or a random-effects model. Several estimators for the random effects variance component (tau^2) are available. The command requires an effect size, its associated standard error, variance, or inverse variance weight, and a categorical variable. {pstd} Meta-analytic regresson (aka, meta-regression) can be performed with the {cmd:mareg} command (see {help mareg}). For a basic meta-analysis returning the overall mean effect size and associated statistics, see {cmd:masum} command (see {help masum}). {pstd} As of Stata version 16.0, Stata has a built-in command for conducting meta-analysis. See {help meta}. {marker description}{...} {title:Acknowledgments} {pstd} {cmd:maanova} was written by David B. Wilson and is an updated version of a command written as a companion to a book on meta-analysis he co-authored with Mark Lipsey (Lipsey & Wilson, 2001). Portions of this program are based on code from Wolfgang Viechtbauer's {it:metafor} package for R. {marker description}{...} {title:References} {pstd} Lipsey, M. W., & Wilson, D. B. (2001). {it} Practical meta-analysis. {sf} Sage.