Designing the methodology: COHORT Studies, B.Pharm, 8th Semester, RGUHS, PCI, Pharm D, Concept: A group of individuals that are all similar in some trait and move forward together as a unit.

1. COHORT STUDIES
Ravinandan A P
Assistant Professor
Sree Siddaganga College of Pharmacy
In association with
Siddaganga Hospital
Tumkur-02

2. Meaning of Cohort
• 1.an ancient Roman military unit, comprising six centuries,
equal to one tenth of a legion.
• Synonyms : unit, outfit, force; More
• 2.a group of people with a shared characteristic.
• "a cohort of civil servants patiently drafting legislation"
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3. COHORT STUDIES
• The term cohort refers to a group of individuals that share
common characteristics
• Latin: cohorts
• – Enclosed yard or company of soldiers
• – All were the same type of soldier
• Concept:
• A group of individuals that are all similar in some trait and move
forward together as a unit.
• (A distinguishing feature of your personal nature)
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4. Definition
• Cohort studies are a type of longitudinal study—an
approach that follows research participants over a period
of time (often many years).
• Specifically, cohort studies recruit and follow participants
who share a common characteristic, such as a particular
occupation or demographic similarity.
• Cohort studies are a type of medical research used to
investigate the causes of disease and to establish links
between risk factors and health outcomes.
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5. Cohort studies
Generally used to compare exposed patients to unexposed patients
Subset population is identified Followed over time
Looking for differences in their outcome
Cohort studies can be performed prospectively or
retrospectively
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7. Example
Smokers Non smokers
Lung cancer
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9. Types of Cohort studies
• Retrospective cohort studies
• Prospective cohort studies
• Ambispective cohort studies
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11. Merits:
- Measures incidence
- Measures strength of relationship
- Controls multiple factors
- Study multiple outcomes
Demerits:
- Larger sample size required (uncommon outcomes)
- Time consuming (delayed drug effects)
- Expensive to conduct
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13. Conclusion
• Cohort studies are types of observational studies in which a
cohort, or a group of individuals sharing some characteristic,
are followed up over time, and outcomes are measured at one
or more time points.
• Cohort studies can be classified as prospective or retrospective
studies, and Ambispective.
• They have several advantages and disadvantages
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