Cross-sectional studies remain a major source of data for research, practice, and policy, despite well-known limitations of this approach in assessing psychopathology. Such studies are especially valuable when the intent is to identify current or recent cases and in repeated studies where trends in rates can be examined. Yet, how well do they identify psychiatric symptoms and syndromes from the past? This is not a trivial question because the accuracy of such classification is important for association studies and, in particular, for clinical neuroscience and genetic studies where the accuracy of phenotypic classification is essential to determining the relationship of predictors and purported outcomes.
Compton WM, Lopez MF. Accuracy in Reporting Past Psychiatric SymptomsThe Role of Cross-sectional Studies in Psychiatric Research. JAMA Psychiatry. 2014;71(3):233-234. doi:10.1001/jamapsychiatry.2013.4111