Question

1. 5. List two advantages and two disadvantages of each of the following study types:
   1. a. Ecologic
   2. b. Cross-sectional
   3. c. Cohort

Answer 1

Ans) a.Advantage of Ecologic studies:

- Can be easy and inexpensive

- Often rely on pre existing data

- Analysis and presentation are generally simple to understand.

- Exposures may truly be population level.

- Can generate new hypothesis for further research.

Disadvantage of Ecologic studies:

- Cannot examine casualty

- Potential and alternative explainations cannot be accounted for or tested.

- Ecological Fallacy

b.Advantage of Cross-sectional study:

- Used to prove and/or disprove assumptions.

- Not costly to perform and does not require a lot of time.

- Captures a specific point in time.

Disadvantage of Cross-sectional study:

- Not used to analyze behavior.

- Useless for determining cause and effect

- timing may not be representative

c. Advantage of cohort study:

- being tailored to collect specific exposure data and may be more complete.

Disadvantage of a prospective cohort study:

- may be the long follow-up period while waiting for events or diseases to occur.