title: Always important--statistical justification for pooling heterogeneous studies?
authors.forename: Dimitrios G
authors.initials: DG
authors.lastname: Goulis
authors.forename: Persefoni-Dimitra
authors.initials: PD
authors.lastname: Kantartzi
authors.forename: Ioannis
authors.initials: I
authors.lastname: Papadimas
mesh_terms: D003627:Data Interpretation, Statistical; D019317:Evidence-Based Medicine; D005260:Female; D006801:Humans; D007248:Infertility, Male / Q000209:etiology* / Q000601:surgery; D008297:Male; D015201:Meta-Analysis as Topic; D011247:Pregnancy; D011256:Pregnancy Outcome; D016032:Randomized Controlled Trials as Topic; D015203:Reproducibility of Results; D012107:Research Design; D016896:Treatment Outcome; D014646:Varicocele / Q000150:complications / Q000601:surgery*