title: [Prevention is more difficult than treatment--and it is not easy to see its effect].
authors.affiliation: Senter for epidemiologisk forskning, Universitetet i Oslo.
authors.forename: D S
authors.initials: DS
authors.lastname: Thelle
mesh_terms: D002986:Clinical Trials as Topic; D006293:Health Promotion; D006801:Humans; D011315:Preventive Medicine; D012307:Risk Factors; D016896:Treatment Outcome
vernacular_title: Forebygging er vanskeligere enn behandling--og det er ikke lett å se at det virker.