Epidemiologists need to identify the source(s) from which to obtain their study-related information when designing a study. Examples of data sources and their applications are summarized in the following table:
Death certificate, hospital record, school absenteeism, etc.
Surveillance, for examples:
- Morbidity and Mortality Weekly Report (MMWR)
- Cancer Surveillance, Epidemiology, and End Results (SEER)
Estimate the prevalence of disease
Ascertain disease and vital status of study population
Estimate frequency of certain cause of death in a population
Estimate the background prevalence of disease
Ascertain cancer occurrence in a study population (SEER data)
Survey, for examples,
- National Health and Nutrition Examination Survey
- National Hospital Discharge Survey
|Provide estimate of health/nutritional status of a population
Personal or Proxy Interview (Questionnaire)
Provide past/current life style, dietary habit, exposure to environmental hazard, etc.
Offer evidence of certain environmental exposure or genetic alteration/polymorphism
Give demographic/social-economic information of a population
White et al (Am J Epidemiol. 2004 Jan 1;159(1):83-93) designed a prospective cohort study to examine the association between vitamin supplement use and cancer risk. To obtain data on supplement use, the authors administered a detailed dietary and supplement questionnaire to each subject at the baseline of the study. Because the study population came from regions covered by the Washington State SEER program cancer registry, the authors planned to monitor the cancer occurrence of the study population by linking the individuals to SEER registry annually by means of social security number during the course of the follow-up.