title: Sample size: how many participants are needed in a trial?
authors: Centre for Medical and Healthcare Education, St George's, University of London, Tooting, London, UK. p.sedgwick@sgul.ac.uk
authors: Philip
authors: P
authors: Sedgwick
mesh_terms: D015992:Body Mass Index; D002675:Child, Preschool; D006701:Home Nursing / Q000379:methods; D006801:Humans; D007223:Infant; D016032:Randomized Controlled Trials as Topic / Q000379:methods / Q000592:standards*; D018401:Sample Size; D016896:Treatment Outcome