title: [Principles in medical statistics. 13. Causal or pragmatic clinical research].
mesh_terms: D008499:Medical Records; D008722:Methods; D010919:Placebos; D012106:Research; D013223:Statistics as Topic; D013997:Time Factors
chemical_list: D010919:Placebos
vernacular_title: Principper i medicinsk statistik. 13. Kausal eller pragmatisk klinisk forskning.