Accuracy and precision of fixed and random effects in meta-analyses of randomized control trials for continuous outcomes.
Res Synth Methods
; 15(1): 86-106, 2024 Jan.
Article
em En
| MEDLINE
| ID: mdl-37751893
ABSTRACT
Meta-analyses of treatment effects in randomized control trials are often faced with the problem of missing information required to calculate effect sizes and their sampling variances. Particularly, correlations between pre- and posttest scores are frequently not available. As an ad-hoc solution, researchers impute a constant value for the missing correlation. As an alternative, we propose adopting a multivariate meta-regression approach that models independent group effect sizes and accounts for the dependency structure using robust variance estimation or three-level modeling. A comprehensive simulation study mimicking realistic conditions of meta-analyses in clinical and educational psychology suggested that imputing a fixed correlation 0.8 or adopting a multivariate meta-regression with robust variance estimation work well for estimating the pooled effect but lead to slightly distorted between-study heterogeneity estimates. In contrast, three-level meta-regressions resulted in largely unbiased fixed effects but more inconsistent prediction intervals. Based on these results recommendations for meta-analytic practice and future meta-analytic developments are provided.
Palavras-chave
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Simulação por Computador
/
Metanálise como Assunto
Tipo de estudo:
Clinical_trials
/
Guideline
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Prognostic_studies
Idioma:
En
Ano de publicação:
2024
Tipo de documento:
Article