title: Statistics Notes: Validating scales and indexes.
authors.affiliation: Department of Public Health Sciences, St George's Hospital Medical School, London SW17 0RE. mbland@sghms.ac.uk
authors.forename: J Martin
authors.initials: JM
authors.lastname: Bland
authors.forename: Douglas G
authors.initials: DG
authors.lastname: Altman
mesh_terms: D006305:Health Status Indicators; D006801:Humans; D015203:Reproducibility of Results; D013223:Statistics as Topic / Q000379:methods*