title: Patient number calculations.
authors.affiliation: Swedish National Competence Center, Musculoskeletal Disorders (NKO), Klinikgatan 22, Lund University Hospital, SE-22185 Lund, Sweden. jr@nko.se
authors.forename: Jonas
authors.initials: J
authors.lastname: Ranstam
mesh_terms: D035843:Biomedical Research / Q000592:standards*; D006801:Humans; D012107:Research Design; D018401:Sample Size