A Comparative Case Vignette Study of Decision Making in Forensic Psychiatric Cases

Abstract

We tested whether the judgment of forensic psychiatric experts differed from that of laypersons. We constructed 18 case vignettes that were rated by 21 psychologists, 14 psychiatrists, and 126 laypeople on the following variables: Insanity by Legal Terms, Risk of Repeated Offense, and Need of Treatment. We found significant differences among laypeople and professionals on all three variables (p = .008, p = .024, and p = .009, respectively), although the differences were dependent on the composition of the case vignettes. Case vignettes containing negative descriptions and/or serious crimes were rated high on all variables by laypeople, whereas the professional groups? ratings varied according to the variations given in the information.

Keywords:

• forensic psychiatry
• decision theory
• expertise
• quality

Acknowledgments

Authors Note: Pål Grøndahl has received research grants for this project from the Norwegian Foundation for Health and Rehabilitation and from The Centre for Research and Education in Forensic Psychiatry, Oslo University Hospital. The authors wish to thank Alv A. Dahl and Petter Laake for their valuable comments on several manuscript drafts.

Notes

^a Psychiatry is a medical specialist degree obtained after five years of training/courses, etc.

^b As for psychiatrists, a specialty in psychology requires five years of training and courses. There are several types of specialists (child, neuropsychological, etc.). Clinical Adult Specialist will be the most frequent specialty in forensic work.