Observational Studies

Which of the following studies only shows patterns, not relationships between exposures and outcomes?

• descriptive studies

• case-control studies

• ecological studies

• cohort studies

True or false: Ecological studies can tell you if the exposure is related to the disease

• True

• False

Prevalence studies are also called

• Cohort studies

• Case-control studies

• Cross-sectional studies

• Ecological studies

How are exposure and outcome measured in cross-sectional studies?

• Data from exposure are collected in the present and data from the outcome are collected in the future

• Data from outcome are collected in the present and exposure data are collected from the past

• Both data from outcome and exposure are collected in the present

This bias is seen when patients cannot accurately recall their exposure status

• Recall bias

• Survivorship bias

• Investigator bias

• Response bias

Which of the following studies can be used for rare diseases

• Cohort study

• Case-control study

• Cross-sectional study

• Descriptive study

Which of the following are characteristics of cohort studies?

• Study participants are people with the disease

• Study participants are people without the disease

• Relative risk cannot be used in this type of study

• Only relative risk can be used in this type of study

Which of the following is true regarding RR and OR?

• As the disease becomes rarer, RR starts to approximate OR

• RR > 1 means that there is a lower probability of the outcome in the exposed group

• RR can be calculated in case-control studies

• RR and OR can be used interchangeably in common diseases