research designs: a short play Jamie Fox Juan M. Lozano Compare - - PowerPoint PPT Presentation

Health research designs: a short play

Jamie Fox Juan M. Lozano

• Compare and contrast

common study designs

• RCT
• Prospective cohort
• Retrospective cohort
• Case control
• Demonstrate interactive

teaching strategies and tools

But once upon at time….

Our PICO question

P In healthy men with lots of hair, I (E) does shampooing daily, C as compared with shampooing once or twice weekly, O increase the risk of baldness (alopecia)? T Type of question: harm T Type of study: open…..

Please take a few minutes (3) to think how you would conduct the following studies to answer the question:

• RCT
• Prospective cohort
• Retrospective cohort
• Case control

Present time Past time Future time Trace Follow

Sample of individuals without disease Sample of individuals with disease

Case-control study

No disease No disease Disease Disease

“Prospective” (concurrent) cohort study

Sample of individuals without disease Exposed to factor Unexposed to factor Exposed to factor Exposed to factor Unexposed to factor Unexposed to factor Exposed to factor Unexposed to factor No disease No disease Disease Disease

“Retrospective” (historical) cohort study

Available in your workshop folder: tab 5 – last page

Present time Past time Future time Follow

Sample of individuals with hair Hairy Hairy Bald Bald

Randomized controlled trial (RCT)

Shampoo daily Shampoo weekly

Present time Past time Future time Follow

Sample of individuals with hair Hairy Hairy Bald Bald

“Prospective” (concurrent) cohort study

Shampoo daily Shampoo weekly

Present time Past time Future time Track

Sample of individuals with hair Hairy Hairy Bald Bald

“Retrospective” (historical) cohort study

Shampoo daily Shampoo weekly

Present time Past time Future time Trace

Sample of bald individuals Sample of hairy individuals

Case-control study

Shampoo daily Shampoo daily Shampoo weekly Shampoo weekly

In a study of risk factors for the development of asthma, investigators enrolled consecutive children during their first newborn well child check. The child’s caretakers were asked whether or not a dog lived in the house. The children were followed for 5 years and the frequency of asthma in children with and without dogs in their house was assessed. What type of study was this?

• a. Randomized controlled trial (RCT)
• b. Prospective cohort
• c. Retrospective cohort
• d. Case control

In a study of risk factors for the development of asthma, investigators accessed records from a primary care clinic’s electronic database. They identified all children with a diagnosis of asthma. They also identified children of similar age and sex who did not have asthma. The investigators then looked to see how many children in each group had dogs in their home before they were diagnosed with asthma. What type of study was this?

• a. Randomized controlled trial (RCT)
• b. Prospective cohort
• c. Retrospective cohort
• d. Case control

In a study of risk factors for the development of asthma, last month investigators accessed records from a primary care clinic’s electronic database from 2000-2008. The investigators determined which children had a dog in their house at the time of their birth. They then looked to see which children developed asthma by their 5th birthday. What type of study was this?

• a. Randomized controlled trial (RCT)
• b. Prospective cohort
• c. Retrospective cohort
• d. Case control

In a study of risk factors for the development of asthma, investigators enrolled families for a study during their newborn visit. After enrollment, the investigators used a computer to determine which families would raise a dog or a goldfish in their home. They followed families for 5 years to see which children developed asthma by their 5th birthday. What type of study was this?

• a. Randomized controlled trial (RCT)
• b. Prospective cohort
• c. Retrospective cohort
• d. Case control

Feature Controlled trial Prospective cohort Retrospective cohort Case - control Who assigns exposure Researcher (randomly, ideally) Other Other Other Direction Exposure to

• utcome

Exposure to

• utcome

Exposure to

• utcome

Outcome to exposure When Now and future Now and future Past Past

Health research designs: a short play

Jamie Fox Juan M. Lozano