Question

In a cohort study with no loss to follow-up, disease status was misclassified as follows:

a. What is the most appropriate relative measure of association to use in this study?

b. Comparing the study population with and without misclassification using this measure of association, is there evidence of information bias?

c. If there is evidence of information bias, is the bias towards or away from the null? Why?

Answer 1

Cohort study used to investigate the causes of disease and to establish links between risk factors and health outcomes.

cohort study can be prospective or retrospective.

Prospective studies are planned in advance and carried out over a fututf period of time.

Retrospective cohort studies look at data that already exist and try to identify risk factors for particular conditions.interpretations are limited because the reserchers cannot go back and gather missing information.

a)they observe large groups of individuals, recording their expoure to certain risk factors to find clues as to the possible causes of diease. So cohort studies are observational.

b) they are based on information bias. Specific data collection

C) the bias towards the null because less control over variables