RA OVS Diabetes

In a case-control study on "Risk factors of diabetic retinopathy," which measure of association is typically calculated?

• Relative Risk

• Odds Ratio

• Risk Difference

• Incidence Rate Ratio

A type II error (β) occurs when:

• You reject a true null hypothesis (false positive)

• You fail to reject a false null hypothesis (false negative)

• You have used an incorrect sampling frame

• You measure an outcome variable inaccurately

Which sampling technique is most appropriate if you want each hospital employee (from staff nurses to janitorial staff) to have an equal chance of selection?

• Convenience sampling

• Snowball sampling

• Simple random sampling

• Quota sampling

Cohort studies are best suited for measuring:

• Prevalence of a disease at a single point in time

• Causal relationships by following exposures over time

• Rare diseases when participants are selected on disease status

• Laboratory experiments with full control over variables

In logistic regression, the outcome variable must be:

• A continuous measure (e.g., blood pressure)

• Time-to-event data (e.g., survival time)

• Ordinal categories (e.g., stage I, II, III)

• Binary categories (e.g., diseased vs. non-diseased)

What is the primary advantage of using stratified sampling over simple random sampling?

• It eliminates sampling bias completely

• It ensures representation of specific subgroups

• It requires a smaller sample size

• It is easier to implement

In a cohort study, what is the primary measure of association used to compare the incidence of disease between exposed and unexposed groups?

• Odds Ratio

• Prevalence Ratio

• Relative Risk

• Attributable Risk

What is the main disadvantage of using convenience sampling in research?

• It may introduce sampling bias

• It requires advanced statistical techniques

• It ensures equal representation of all groups

• It is time-consuming

In a randomized controlled trial, what is the purpose of blinding participants?

• To minimize placebo effects

• To enhance data collection accuracy

• To reduce selection bias

• To ensure equal treatment allocation

Which statistical test is most appropriate for comparing means between two independent groups?

• Paired t-test

• Chi-square test

• Independent t-test

• ANOVA