Question

How does a nested case-control study work in terms of steps?

A) Select cases, Identify controls, Collect exposure data, Analyze data
B) Define cohort, Identify cases within the cohort, Match controls to cases, Collect exposure data
C) Randomly assign participants, Measure outcomes, Assign exposures, Analyze data
D) Identify cases within a cohort, Select controls from the cohort, Collect exposure data, Analyze data

Answer 1

A nested case-control study is an observational study that follows a defined cohort over time, identifies cases and matched controls within the cohort, collects past exposure data, and analyzes the data to find associations with the outcome. The correct sequence of steps for a nested case-control study is to identify cases within a cohort, select controls, collect exposure data, and analyze the data.

Step-by-step explanation:

A nested case-control study is a type of observational study that is used to identify factors that may contribute to a particular outcome in a previously defined cohort that has been followed over time. This approach can help to assess the potential impact of suspected risk factors in a cost-effective and efficient manner. Here are the typical steps involved in a nested case-control study:

1. Define a cohort of individuals to follow over time.
2. Within the cohort, identify individuals who develop the outcome of interest (cases).
3. Select controls from the same cohort who do not have the outcome. These controls are often matched to cases based on certain characteristics like age, sex, or other variables.
4. Collect and analyze past exposure data for both cases and controls to seek associations between exposures and the outcome.

Thus, the proper sequence of steps in a nested case-control study is D) Identify cases within a cohort, Select controls from the cohort, Collect exposure data, Analyze data.