cross-posted from: https://lemmy.ml/post/1491937
Using surveys, cognitive tests and brain imaging, researchers have identified a type of depression that affects about a quarter of patients. The goal is to diagnose and treat the condition more precisely.
I was thinking of the sample in relation to the population being studied. There are reportedly over 21 million people in the US diagnosed with depression. 1000 people is representative of less than 0.005% of that group.
Yes, I’m aware. Sample sizes to get a 95% confidence interval are significantly smaller in most cases than the average person thinks. See https://en.wikipedia.org/wiki/Sample_size_determination and the section on required sample size for hypotheses tests. There’s even sample size calculators online you can find that’ll spit this number for a 95% CI out for you. Personally I think given that information, it’s pretty unlikely the author made that error in a peer reviewed paper where reviewers are certainly aware as well
Just wait until people hear about all the medical studies with sample size goals of twelve, considered an adequate sample size for medical procedure studies and medical device studies.
Thanks. :) My curiosity about the other factors remains. Perhaps they will add more information about this next time.
Yeah, that’s totally fair to question. I mentioned above, but it depends on sample selection and study design moreso than the actual number 👍