In short, the claim is that the experience of psychological practitioners allows them to go beyond the aggregate relationships that have been uncovered by research. The claim that clinical prediction is efficacious is, thus, easily test-able. Unfortunately, the claim has been tested, and it has been falsified. Research on the issue of clinical versus actuarial prediction has been consistent. Since the publication in 1954 of Paul Meehl’s classic book Clinical Versus Statistical Prediction actuarial prediction has been found to be superior to clinical prediction (Kahneman, 2011; Morera & Dawes, 2006; Swets et al., 2000; Tetlock, 2005).

The error of implying that psychological predictions can be made at the level of the individual is often made by clinical psychologists themselves, who sometimes mistakenly imply that clinical training confers an “intuitive” ability to predict an individual case. Instead, decades’ worth of research has consistently indicated that actuarial prediction (prediction in terms of group statistical trends) is superior to clinical prediction in accounting for human behavior

Keith E. Stanovich (member of CFAR's board of advisors) in How to Think Straight About Psychology