title: Numbers needed to treat derived from meta-analyses--sometimes informative, usually misleading.
authors.affiliation: Department of Primary Care and Population Sciences, Royal Free and University College Medical School, University College London, London NW3 2PF.
authors.forename: L
authors.initials: L
authors.lastname: Smeeth
authors.forename: A
authors.initials: A
authors.lastname: Haines
authors.forename: S
authors.initials: S
authors.lastname: Ebrahim
mesh_terms: D002986:Clinical Trials as Topic; D003627:Data Interpretation, Statistical; D006801:Humans; D015201:Meta-Analysis as Topic; D017063:Outcome Assessment, Health Care; D018401:Sample Size