Related Experiment Video
Updated: Jun 8, 2026

Characterization of Complex Systems Using the Design of Experiments Approach: Transient Protein Expression in Tobacco as a Case Study
Published on: January 31, 2014
Methods in epidemiology: observational study designs
1Department of Pharmacy Practice, Raabe College of Pharmacy, Ohio Northern University, Ada, Ohio 45810, USA.
Abstract:
This article is the first of a three-part series intended to enhance clinical pharmacists' understanding of methods frequently used in epidemiologic research and their applications. The basic tenets of epidemiology and uses for data derived from epidemiologic studies are given, along with a high-level overview of the differences between experimental and observational study designs. The defining characteristics of each of the observational study designs (case report or case series, ecologic, cross-sectional, cohort, case-control, nested case-control, and case-cohort) and the resultant strengths and limitations of the study designs are presented. Applications for observational studies in pharmacoepidemiology (including the case-crossover and case-time-control study designs) are discussed. Finally, points to consider when evaluating data from observational studies are addressed.
More Related Videos
06:55Inverse Probability of Treatment Weighting (Propensity Score) using the Military Health System Data Repository and National Death Index
Published on: January 8, 2020
09:33Visualizing Field Data Collection Procedures of Exposure and Biomarker Assessments for the Household Air Pollution Intervention Network Trial in India
Published on: December 23, 2022
Related Concept Videos
Study Designs in Epidemiology
Observational studies are those where the researcher does not intervene but rather observes natural variations. They include cross-sectional, cohort, and case-control studies.
Observational Studies
There are three types of observational studies – Prospective, retrospective, and cross-sectional.
Prospective Study
Prospective studies, also known as longitudinal or cohort studies, are carried out by collecting future data from groups sharing similar characteristics. One example of...
Introduction to Epidemiology
Statistical Methods for Analyzing Epidemiological Data
Study Design in Statistics
Does aspirin reduce the risk of heart attacks? Is one brand of fertilizer more effective at growing roses than another? Is fatigue as dangerous to a driver as the influence of alcohol? Questions like these are answered using randomized experiments with proper...
Data Collection by Observations
An astronomer viewing the motion and brightness of stars in the sky and recording the data is an example of observational data collection. A botanist recording...