How do physicians decide to treat: an empirical evaluation of the threshold model
1 Department of Internal Medicine, Division of Evidence-based Medicine and Health Outcomes Research, University of South Florida, Tampa, FL, USA
2 Department of Health Outcomes and Behavior, Moffitt Cancer Center & Research Institute, Tampa, FL, USA
3 Department of Hematology, Moffitt Cancer Center & Research Institute, Tampa, FL, USA
4 De Montfort University, Leicester, UK
5 Indiana University Northwest, Department of Mathematics, Gary, IN, USA
6 College of Nursing, University of South Florida, Tampa, FL, USA
7 Center for Advanced Medical Learning & Simulations, University of South Florida, Tampa, FL, USA
8 USF Health, 3515 East Fletcher Avenue, MDT 1202, Tampa, FL 33612, USA
BMC Medical Informatics and Decision Making 2014, 14:47 doi:10.1186/1472-6947-14-47Published: 5 June 2014
According to the threshold model, when faced with a decision under diagnostic uncertainty, physicians should administer treatment if the probability of disease is above a specified threshold and withhold treatment otherwise. The objectives of the present study are to a) evaluate if physicians act according to a threshold model, b) examine which of the existing threshold models [expected utility theory model (EUT), regret-based threshold model, or dual-processing theory] explains the physicians’ decision-making best.
A survey employing realistic clinical treatment vignettes for patients with pulmonary embolism and acute myeloid leukemia was administered to forty-one practicing physicians across different medical specialties. Participants were randomly assigned to the order of presentation of the case vignettes and re-randomized to the order of “high” versus “low” threshold case. The main outcome measure was the proportion of physicians who would or would not prescribe treatment in relation to perceived changes in threshold probability.
Fewer physicians choose to treat as the benefit/harms ratio decreased (i.e. the threshold increased) and more physicians administered treatment as the benefit/harms ratio increased (and the threshold decreased). When compared to the actual treatment recommendations, we found that the regret model was marginally superior to the EUT model [Odds ratio (OR) = 1.49; 95% confidence interval (CI) 1.00 to 2.23; p = 0.056]. The dual-processing model was statistically significantly superior to both EUT model [OR = 1.75, 95% CI 1.67 to 4.08; p < 0.001] and regret model [OR = 2.61, 95% CI 1.11 to 2.77; p = 0.018].
We provide the first empirical evidence that physicians’ decision-making can be explained by the threshold model. Of the threshold models tested, the dual-processing theory of decision-making provides the best explanation for the observed empirical results.