Referral Decision Making of General Practitioners:A Signal Detection Study

Background. Signal detection theory (SDT) describes how respondents categorize ambiguous stimuli over repeated trials. It measures separately ‘‘discrimination’’ (ability to recognize a signal amid noise) and ‘‘criterion’’ (inclination to respond ‘‘signal’’ v. ‘‘noise’’). This is important because respondents may produce the same accuracy rate for different reasons. We employed SDT to measure the referral decision making of general practitioners (GPs) in cases of possi- ble lung cancer. Methods. We constructed 44 vignettes of patients for whom lung cancer could be considered and esti- mated their 1-year risk. Under UK risk-based guidelines, half of the vignettes required urgent referral. We recruited 216 GPs from practices across England. Practices differed in the positive predictive value (PPV) of their urgent refer- rals (chance of referrals identifying cancer) and the sensitivity (chance of cancer patients being picked up via urgent referral from their practice). Participants saw the vignettes online and indicated whether they would refer each patient urgently or not. We calculated each GP’s discrimination (d0) and criterion (c) and regressed these on practice PPV and sensitivity, as well as on GP experience and gender. Results. Criterion was associated with practice PPV: as PPV increased, GPs’c also increased, indicating lower inclination to refer (b = 0.06 [0.02–0.09]; P = 0.001). Female GPs were more inclined to refer than male GPs (b = 20.20 [20.40 to 20.001]; P = 0.049). Average discrimination was modest (d 0 = 0.77), highly variable (range, 20.28 to 1.91), and not associated with practice referral performance. Conclusions. High referral PPV at the organizational level indicates GPs’ inclination to avoid false positives, not bet- ter discrimination. Rather than bluntly mandating increases in practice PPV via more referrals, it is necessary to increase discrimination by improving the evidence base for cancer referral decisions

How can the usefulness of capability assessments be improved?

Capability assessments are used in disaster risk management to facilitate decision making regarding capability increasing measures. Recent studies suggest that two factors might determine their usefulness for decision making: whether they include descriptions of an actor's available resources, and how well the actor can accomplish a specific task in case of a disaster. The experimental study presented here aimed at investigating the extent to which these factors influence the perceived usefulness for decision making of four hypothetical capability assessments, differing in whether they contain information regarding the two factors. 89 participants from the Swedish fire and recue services were randomly assigned to rate the perceived usefulness of one of the four versions and the results show that the presence of both factors makes assessments more useful, and resources are especially important to include

The Methodology of Forensic Neuroscience

Insanity is a distinctive element of criminal law because it brings together two very different disciplines, psychiatry and psychology on the one hand and the law on the other. It might strongly benefit from the introduction of structural neuroimaging, that, however, had so far a limited translational impact. Brain imaging purports to demonstrate functional status and thereby it can be useful to provide a scientific explanation for the clinical symptoms strenghtening the medico-legal reasoning. Despite international cases using brain imaging to support diminished responsibility, in Italy there are still a lot of controversies. Is the neuroscientific logic deterministic? How may the classic psychiatric/neurologic examination and neuroscientific evidence work side by side? Are the symptoms not legally relevant really not relevant? Could the study of the brain inform the clinical diagnosis? Could the study of the brain inform the expert opinion on responsibility and insanity? In this chapter, we describe the cognitive and behavioral profile of a defendant charged with murder, as well as his brain imaging correlates. Through the analysis of this real forensic case, we address the above questions and conclude that neuroscience may strengthen the results of psychiatric evaluations, thus reducing uncertainty in the forensic settings. We claim that besides the clinical diagnosis, the study of the brain allows a better understanding of the individual acts