A case-control study that compares patients who have a disease with patients who do not have the disease and looks back retrospectively (back in time to find the relative risk factors) to compare how frequently the exposure to a risk factor is present in each group to determine the relationship between the risk factor and the disease, (Tenny et al., 2022).
The three essential features related to selecting cases and controls entail, identifying and or selecting individuals in whom the distribution of exposure status would be the same as that of the cases in the absence of an exposure disease association, participants are based on their outcome status. The cases and controls should have the same distribution of exposure. It is essential that the case definition is clearly defined at the outset of the investigation to ensure that all cases included in the study are based on the same diagnostic criteria. The source of controls is dependent on the source of cases. Situations where cases and controls can be violated through selection bias. According to Tenny et al., (2022) “The researcher must recognize the potential for failing to identify confounding variables or exposures, introducing the possibility of confounding bias, which occurs when a variable that is not being accounted for that has a relationship with both the exposure and outcome. This can cause a researcher to accidentally be studying something that is not accounted for but that may be systematically different between the groups, (Hennekens & Buring, 1987).
The limitations of using questionnaires in determining exposure status are that data collected might be time-consuming, and longer for participants complete questionnaires. Untruthful answers when filling out the questions and not fully understanding what is asked. Strategies for collecting information are to make sure questions are short, clear, and to the point. Make sure all questions are asked to address the aims of the research, (Mcleod, 2018).
Hennekens CH, Buring JE. Epidemiology in Medicine, Lippincott Williams & Wilkins, 1987. Introduction to study designs, case-control studies. Retrieved From: https://www.healthknowledge.org.uk/
Mcleod, S., (2018). Questionnaire: definition, examples, design, and types. Simply Psychology. https://www.simplypsychology.org/questionnaires.html