Cohort Studies

Cohort Studies is a study design where one or more people (called cohorts) are followed and subsequent status evaluations with respect to a disease or outcome are conducted to determine which participants’ exposure characteristics (risk factors) are associated. As the study is conducted, the outcome from participants in each cohort is measured and relationships with specific characteristics determined. Dr. Alex Jimenez’s collection of articles discusses a variety of cohort studies associated with musculoskeletal disorders like sciatica.

Cohort Study facts:

Cohort studies usually observe large groups of individuals and record their exposure to certain risk factors to find clues as to the possible causes of disease.
They can be prospective studies that gather data going forward, or retrospective cohort studies, which look at data already collected.
This type of research can also help identify social factors that influence health.

The fundamentals of a cohort study are:

a. Identify people who are free of disease at the beginning of the study
b. Assemble cohorts of exposed and unexposed individuals
c. Follow cohorts for the development of incident outcomes
d. Compare the risks of incident outcomes in each cohort

Advantages

Cheaper & easier than a randomized controlled trial (RCT)
Standardization of criteria/outcome is possible
Subjects can be matched, which limits the influence of confounding variables

Disadvantages

Cohorts can be difficult to identify from confounding variables
No randomization, which means that imbalances could exist
Blinding/Masking is difficult
The outcome of interest can take a long time to occur