Advanced Statistical Methods in Biometric Research.

Clinical predictions made by mental health practitioners are compared with those using statistical approaches. Sixty-seven studies were identified from a comprehensive search of 56 years of research; 92 effect sizes were derived from these studies. The overall effect of clinical versus statistical prediction showed a somewhat greater accuracy for statistical methods. The most stringent sample of studies, from which 48 effect sizes were extracted, indicated a 13% increase in accuracy using statistical versus clinical methods. Several variables influenced this overall effect. Clinical and statistical prediction accuracy varied by type of prediction, the setting in which predictor data were gathered, the type of statistical formula used, and the amount of information available to the clinicians and the formulas. Recommendations are provided about when and under what conditions counseling psychologists might use statistical formulas as well as when they can rely on clinical methods. Implications for clinical ...

https://www.oocities.org/g-lam/tcp2006aegisdottiretalclinicaljudgment.pdf

The Meta-Analysis of Clinical Judgment Project: Fifty-Six Years of Accumulated Research on Clinical Versus Statistical Prediction

Multiple comparison in psychological research.

Clinical and educational experience is one of the most commonly studied variables in clinical judgment research. Contrary to clinicians' perceptions, clinical judgment researchers have generally concluded that accuracy does not improve with increased education, training, or clinical experience. In this meta-analysis, the authors synthesized results from 75 clinical judgment studies where the experience of 4,607 clinicians was assessed in relation to the accuracy of their judgments about mental health (e.g., diagnosis, prognosis, treatment) and psychological issues (e.g., vocational, personality). The authors found a small but reliable effect, d = .12, showing that experience, whether educational or clinical, is positively associated with judgment accuracy. This small effect was robust across several tested moderator models, indicating experienced counselors and clinicians acquire, in general, almost a 13% increase in their decision-making accuracy, regardless of other factors. Results are discussed in lig...

Richard B. McHugh

Papers

Methodology for the comparison of clinical with actuarial predictions.

Comment on "Scales and Statistics: Parametric and Nonparametric."

The "postmortem" testing of experimental comparisons.

The interval estimation of a true score.