Interpreting meta-regression: application to recent controversies in antidepressants' efficacy.
Stat Med
; 32(17): 2875-92, 2013 Jul 30.
Article
en En
| MEDLINE
| ID: mdl-23440635
ABSTRACT
A recent meta-regression of antidepressant efficacy on baseline depression severity has caused considerable controversy in the popular media. A central source of the controversy is a lack of clarity about the relation of meta-regression parameters to corresponding parameters in models for subject-level data. This paper focuses on a linear regression with continuous outcome and predictor, a case that is often considered less problematic. We frame meta-regression in a general mixture setting that encompasses both finite and infinite mixture models. In many applications of meta-analysis, the goal is to evaluate the efficacy of a treatment from several studies, and authors use meta-regression on grouped data to explain variations in the treatment efficacy by study features. When the study feature is a characteristic that has been averaged over subjects, it is difficult not to interpret the meta-regression results on a subject level, a practice that is still widespread in medical research. Although much of the attention in the literature is on methods of estimating meta-regression model parameters, our results illustrate that estimation methods cannot protect against erroneous interpretations of meta-regression on grouped data. We derive relations between meta-regression parameters and within-study model parameters and show that the conditions under which slopes from these models are equal cannot be verified on the basis of group-level information only. The effects of these model violations cannot be known without subject-level data. We conclude that interpretations of meta-regression results are highly problematic when the predictor is a subject-level characteristic that has been averaged over study subjects.
Palabras clave
Texto completo:
1
Ejes tematicos:
Pesquisa_clinica
Banco de datos:
MEDLINE
Asunto principal:
Modelos Lineales
/
Metaanálisis como Asunto
/
Antidepresivos
Tipo de estudio:
Clinical_trials
/
Prognostic_studies
/
Systematic_reviews
Límite:
Humans
Idioma:
En
Año:
2013
Tipo del documento:
Article