An Introduction to Epidemiology for Health Professionals

"Whatareimportantprognosticfactors?"Answerstosuchquestionsprovidethe basisforbetterpreventionandtreatmentofdiseases. Many people contributed to the writing of this book: medical students in Denmark,studentsofepidemiologyattheIEAEEPEsummercourseinFlorence, Italy,andstudentsofpublichealthinLosAngeles. Withouttechnicalassistance v vi Preface fromGitteNielsen,JenadeShelley,NinaHoheandPamMasangkaythebookwould neverhavematerialized. LosAngeles,California JørnOlsen Odense,Denmark KaareChristensen IowaCity,Iowa JeffMurray Stockholm,Sweden AndersEkbom Contents Part I Descriptive Epidemiology 1 Measures of Disease Occurrence . . . . . . . . . . . . . . . . . . . 3 IncidenceandPrevalence . . . . . . . . . . . . . . . . . . . . . . . . 4 Incidence. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 RatesandDynamicPopulations . . . . . . . . . . . . . . . . . . . . . 7 CalculatingObservationTime. . . . . . . . . . . . . . . . . . . . . . 9 Prevalence,Incidence,Duration . . . . . . . . . . . . . . . . . . . . . 10 MortalityandLifeExpectancy . . . . . . . . . . . . . . . . . . . . . 11 LifeExpectancy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 2 Estimates of Associations . . . . . . . . . . . . . . . . . . . . . . . 15 3 Age Standardization. . . . . . . . . . . . . . . . . . . . . . . . . . 19 4 Causes of Diseases . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 5 Descriptive Epidemiology in Public Health. . . . . . . . . . . . . . 29 GraphicalModelsofCausalLinks . . . . . . . . . . . . . . . . . . . 33 References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 6 Descriptive Epidemiology in Genetic Epidemiology. . . . . . . . . 37 OccurrenceDatainGeneticEpidemiology . . . . . . . . . . . . . . . 37 ClusteringofTraitsandDiseasesinFamilies . . . . . . . . . . . . . .