Epidemiology

EPIDEMIOLOGY Definition Historical Background Aims Other Uses CONCEPTS OF CAUSE Definition Types of Association The Web of Causation GROUPING OF ILL PERSONS AND CLASSIFICATION OF DISEASE Grouping of Ill Persons Classification of Disease Entities MEASURES OF DISEASE FREQUENCY Incidence and Prevalence Crude, Specific, and Standardized Rates Specification of Time Interrelation of Measures Selection of Measures STRATEGIES OF EPIDEMIOLOGY Describing the Distribution of Disease Forming Hypotheses Stating a Hypothesis Testing Hypotheses TIME Short-Term Changes Specification of Time Secular Changes Generational (Cohort) Secular Time Trends Cyclic Changes PLACE International Comparisons Variation Within Countries Local Clustering of Disease Clustering by Time and Place PERSON Age Gender Race and Ethnic Group Migration Socioeconomic Status Occupation Marital Status Religion COHORT STUDIES Types of Cohort Measures of Effect in Cohort Studies Choice of Study Cohorts Obtaining Data on Exposure Selection of Comparison Groups Follow-Up Analysis Interpretation CASE-CONTROL STUDIES Theoretical Foundation of Case-Control Studies Selection of Cases Considerations for Selection of Controls Information on Exposure Confounding and Statistical Power Sources and Methods for Control Selection Analysis Attributable Rates and Fractions and Their Applicability in Case-Control Studies Interpretation