Session 13 Sampling Methods (cross Sectional And Ecological Study)

Question 1

Inference

Answer 1

A conclusion based on gathered evidence and reasoning

Question 2

Observational studies

Answer 2

The research watches and records what happens naturally without interfering which allows researchers to make strong inferences.

Question 3

Experimental studies

Answer 3

Cause and effect/ the researcher steps in and changes something to see if it causes a certain result

Question 4

Randomized controlled trials (RCTs)

Answer 4

When participants are randomly assigned to groups to compare the effects of treatment

Question 5

Non-randomized controlled trials

Answer 5

Where participants are assigned by hand to compare different outcomes

Question 6

Cohort studies

Answer 6

Follows a group of people overtime to see how certain factors effect outcomes

Question 7

Case-control studies

Answer 7

Follows diseased people backwards to see possible correlations to overall disease

Question 8

Cross sectional studies

Answer 8

An observational study that examines data from a snapshot in time without any follow up.
- can be repeated cross sectional studies to measure change in population

Question 9

Ecological studies

Answer 9

Looks at big groups/populations over individual trends/patterns

Question 10

Case report

Answer 10

Detailed report of specific features of a case

Question 11

Case series

Answer 11

Systematic review of common features of a small number of cases
- advantage: cost efficient
Disadvantage: no comparison and no specific research question/aim

Question 12

Population census

Answer 12

A type of cross sectional study that is done in a single point in time (every 10 years) where government counts everyone in the population to get data on them. This helps calculate rates and makes sure changing results apply to the whole population.
- huge efforts - people can be difficult to find or count and may not want to provide data

Question 13

What does ecological studies look at?

Answer 13

Looks at entire populations of people instead of individual people. Focuses on finding patterns across groups rather than a single person.

Question 14

What are strengths of ecological studies?

Answer 14

1) fast and easy
2) statistical analysis and interpretations are straightforward
3) good at coming up with hypotheses and rejecting ones that don’t fit

Question 15

What are weakness of ecological studies?

Answer 15

1) hard to tell if exposure came before or after the outcome
2) can have a lot of missing data due to lack of follow up
3) findings can only be interpreted from a group level not an individual level

Question 16

Ecological fallacy

Answer 16

Making incorrect conclusions about individuals based on analyses of group level data.