Question

4 Name: Triming Key differentiating Measures Measures frequency association of of Limitations Study DesignDescription characteristics associationStrengths Cross-sectional Case-control Retrospective Cohort Prospective Cohort Experimental
would do all of them please

Answer 1

Cross sectional

Description - is a type of observational study that analyses data from a population at a specific point of time.

Time - same point of time or without regard to differences in time

Key differentiating characteristics - the data is collected at the same time from people who are similar in other characteristics but different in age , income, and geographical location.

Measured of frequency - fictive data

Measured of association - chronic diseases study or long lasting risk factors.

Strength- use to prove  or disprove the assumptions

Cheap and quick and multiple variables at the time of data collection

Limitations - no evidence in relationship between exposure and outcome

Without longitudinal data not possible in true and effect relationship.

CASE CONTROL

Description- they are retrospective .defining two groups at the start. One with the outcome and another without outcome

Time - do not allow estimated time

Key factors- relative size of case and contr groups

Measured of frequency- number of new cases and number of existing cases.

Measured of association - odds ratio

Strength - efficient for rare cases , less cost and less time consuming

Limitations - they subject to selection bias

Inefficient for rare exposure and do not allow calculation of incidence.