In this article, we describe a new individual patient data meta-analysis postestimation command, ipdforest. The command produces a forest plot following a one-stage meta-analysis with xtmixed or xtmelogit. (These commands have been renamed in Stata 13 to mixed and meqrlogit, respectively; ipdforest is currently not compatible with the new names.) The overall effect is obtained from the preceding mixed-effects regression and the study effects from linear or logistic regressions on each study, which are executed within ipdforest. Individual patient data meta-analysis models with Stata are discussed.
HardyR. J., and ThompsonS. G.1998. Detecting and describing heterogeneity in meta-analysis. Statistics in Medicine17: 841–856.
2.
HarrisR. J., BradburnM. J., DeeksJ. J., HarbordR. M., AltmanD. G., and SterneJ. A. C.2008. metan: Fixed- and random-effects meta-analysis. Stata Journal8: 3–28.
3.
HigginsJ. P. T., ThompsonS. G., DeeksJ. J., and AltmanD. G.2003. Measuring inconsistency in meta-analyses. British Medical Journal327: 557–560.
4.
HunterJ. E., and SchmidtF. L.2000. Fixed effects vs. random effects meta-analysis models: Implications for cumulative research knowledge. International Journal of Selection and Assessment8: 275–292.
5.
KontopantelisE., and ReevesD.2009. MetaEasy: A meta-analysis add-in for Microsoft Excel. Journal of Statistical Software30: 1–25.
6.
KontopantelisE., and ReevesD.2010. metaan: Random-effects meta-analysis. Stata Journal10: 395–407.
7.
MathewT., and NordströmK.2010. Comparison of one-step and two-step meta-analysis models using individual patient data. Biometrical Journal52: 271–287.
8.
MittlböckM., and HeinzlH.2006. A simulation study comparing properties of heterogeneity measures in meta-analyses. Statistics in Medicine25: 4321–4333.
9.
TurnerR. M., OmarR. Z., YangM., GoldsteinH., and ThompsonS. G.2000. A multilevel model framework for meta-analysis of clinical trials with binary outcomes. Statistics in Medicine19: 3417–3432.
10.
WhiteheadA.2002. Meta-Analysis of Controlled Clinical Trials.Chichester, UK: Wiley.
