enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Ecological study - Wikipedia

    en.wikipedia.org/wiki/Ecological_study

    Ecological studies are particularly useful for generating hypotheses since they can use existing data sets and rapidly test the hypothesis. The advantages of the ecological studies include the large number of people that can be included in the study and the large number of risk-modifying factors that can be examined.

  3. Hierarchy of evidence - Wikipedia

    en.wikipedia.org/wiki/Hierarchy_of_evidence

    2a: Systematic reviews (with homogeneity) of cohort studies; 2b: Individual cohort study or low quality randomized controlled trials (e.g. <80% follow-up) 2c: "Outcomes" Research; ecological studies; 3a: Systematic review (with homogeneity) of case-control studies; 3b: Individual case-control study; 4: Case series (and poor quality cohort and ...

  4. Cohort study - Wikipedia

    en.wikipedia.org/wiki/Cohort_study

    A cohort study is a particular form of longitudinal study that samples a cohort (a group of people who share a defining characteristic, typically those who experienced a common event in a selected period, such as birth or graduation), performing a cross-section at intervals through time.

  5. Observational study - Wikipedia

    en.wikipedia.org/wiki/Observational_study

    Cross-sectional study: involves data collection from a population, or a representative subset, at one specific point in time. Longitudinal study: correlational research study that involves repeated observations of the same variables over long periods of time. Cohort study and Panel study are particular forms of longitudinal study.

  6. Case–control study - Wikipedia

    en.wikipedia.org/wiki/Case–control_study

    The case–control study design is often used in the study of rare diseases or as a preliminary study where little is known about the association between the risk factor and disease of interest. [8] Compared to prospective cohort studies they tend to be less costly and shorter in duration. In several situations, they have greater statistical ...

  7. Prospective cohort study - Wikipedia

    en.wikipedia.org/wiki/Prospective_cohort_study

    Case–control study versus cohort on a timeline. "OR" stands for "odds ratio" and "RR" stands for "relative risk". A prospective cohort study is a longitudinal cohort study that follows over time a group of similar individuals ( cohorts ) who differ with respect to certain factors under study to determine how these factors affect rates of a ...

  8. Nutritional epidemiology - Wikipedia

    en.wikipedia.org/wiki/Nutritional_epidemiology

    An ecological study is an observational study that studies risk-modifying factors on health outcomes of populations based on their geographical and/or temporal ecological state. Ecological studies are useful in studying patterns of disease in large populations however may not accurately reflect true associations between individuals within those ...

  9. Retrospective cohort study - Wikipedia

    en.wikipedia.org/wiki/Retrospective_cohort_study

    A retrospective cohort study, also called a historic cohort study, is a longitudinal cohort study used in medical and psychological research. A cohort of individuals that share a common exposure factor is compared with another group of equivalent individuals not exposed to that factor, to determine the factor's influence on the incidence of a ...