Case control studies

[gracecharron]

Thank you! Your lecture helped me a lot to understand a case-control study that I have learnt from my instructor.

[rathodk]

Kitty had a doubt in case control studies... :D

[samphonnetgamgee]

Very good, thank you! Your cat's approval's there, too. 😄

[coolkitty]

What do you mean by "exposure"? Sorry if you explained in it a different video.

[sarmiladhakal]

What is the difference between case control study and retrospective cohort study ?

[aidenmeyer]

I have a science fair coming up at my high school and I am really interested in doing a Case-Control Study. I have two questions, first, I wanted to do a study to see if suffering from a traumatic injury that resulted in the fracture increases a person chance of developing Rheumatoid Arthritis. Would this be a good study? and Also about finding Cases and Controls how would suggest that I set out to do this?

[kuchbhi]

Thank you so much mam, this really helped.

[manochehrteimory]

No, I think there is some kind of weak comprehension with respect to the difference between case-control studies and cohort studies. Case-control study is a type of cross-sectional study, in which you select the cases intentionally. You have the data from the cases only once, not more. For instance, in the case-control study, you know that there are two cases: one with the disease and another without disease. You know that they have had previous exposure to something or not, but you do not know their health status at the time you think they exposed. you do not know that they were in the past healthy or had the disease in the beginning as you do miss the data regarding their health status in the past. In another word, from every type of data (health/disease status and exposure/no-exposure), you have only one data in time. But in cohort study, regardless of retrospective or prospective design of the study, you have twice, three times and more of each data in time. For instance, you have data that 2 years ago the cases or group that they exposed to something were all disease-free because you have the data of that time, then 1 year ago, 60% of them were found to have the disease; and now there are 75% of the exposed groups are suffering from the disease. Similarly, you have repeated measurement of the data for non-exposed group.