Design This was a retrospective observational study of medical students’ performance with standardized patients. The Institutional Review Board approved the study.
Subjects and Setting
After the third-year core clerkships, all University of California, San Francisco (UCSF) students are required to take the Clinical Performance Examination (CPX). The CPX is an eight-station comprehensive standardized patient examination developed by the eight medical schools comprising the California Consortium for the Assessment of Clinical Competence. Each CPX encounter lasts 15 minutes and is videotaped. After each encounter, standardized patients complete a criterion-based checklist evaluating students’ history taking, physical examination, communication and information sharing skills. Checklist accuracy by the consortium’s standardized patients exceeds 95%.22
A total of 143 UCSF medical students comprising the class of 2006 participated in the May–June 2005 CPX. The class of 2006 was 63% female. The self-described racial makeup of the class was 48% White, 33% Asian, 3% Black, 2% Native American, 6% other race, 2% unknown, and 6% multirace. We used a random number generator to select a 60-student probability sample for the study. This sample size (n
60) gave adequate (80%) power to detect correlations of 0.35 and outstanding power (99%) to detect correlations of 0.5 or larger. All CPX encounters were video-recorded as part of usual exam procedure. Videotapes of the four study cases from the 60 randomly selected students were transcribed for analysis.Communications skills cases and rating instrument: For this study, we selected four CPX cases that highlighted medical conditions likely to prompt decision-making opportunities regarding disease management or behaviors. (Appendix 1
, available online) For shared decision-making to occur, one necessary prerequisite is a decision with multiple options4,23
. Standardized patients participated in 17 hours of training over five sessions. Two different standardized patients portrayed the hypertension case and three portrayed each of the other three cases. The trainer assessed the standardized patients for consistency of portrayal and checklist accuracy during training and the exam.The CPX case checklists used by the standardized patients included seven communication items (listening, rapport building, professional demeanor, and addressing the patient’s perspective and needs) based on the Common Ground checklist. This checklist was previously shown to have high reliability (rho
> 0.80) when completed by trained raters and high correlation with global ratings of communication by faculty experts (r
Standardized patients scored the communication items from 0 to 1.0 on a six-point scale (0, 0.2, 0.4, 0.6, 0.8, 1.0, as defined in Appendix 2
, available online), with total scores reported as percentages (maximum 100%).Shared decision-making coding: Four investigators (KEH, AF, AT, GS) coded shared decision-making using a coding manual (Appendix 3
, summary available online) and coding worksheet (Appendix 4
, available online) from an instrument used to code physician–patient encounters.15
The worksheet includes checkboxes for decision moment identification and each of the key dimensions of shared decision-making within a single decision moment: exploration/articulation of perspective (beliefs, values), information sharing, and explicit closure, each of which could be done by the student, standardized patient, or both. In contrast to some other published shared decision-making scales,6,11,17
we captured both the student physician’s sharing of beliefs and values and the students’ responses to information from the patient. A single worksheet was used for each decision moment, which begins when a suggestion is made to change behavior or consider medical therapy or testing. Each dimension was marked as present or absent for each decision discussed by the student and standardized patient; each dimension was attributed to the student or patient only once per decision moment.Examples of shared decision-making decision moment discussions between students and standardized patients are shown in Text box 1. There was no maximum number of decision moments per case; it was also possible for an encounter to have none. Each of the 240 encounters was coded by two coders, and reconciled by consensus discussion between the two coders, or with other coders in the event of discrepancy, which was rare.Text box 1: Shared decision-making decision moment examples.
Text box 1
Shared Decision-Making Decision Moment Examples
For analysis, we defined shared decision-making as a decision moment that included at least four of the possible ten decision-making elements (in addition to decision identification) on the worksheet (Appendix 4
, available online) in which one of the four was closure of the decision by the patient. Inclusion of at least four elements ensures participation by both student and patient with presence of essential domains of shared decision-making (exchange of feelings and beliefs, exchange of information, and closure). This cutoff is similar to that used in prior literature, with a slightly lower cutoff due to students’ earlier point in training than practicing physicians.15
Closure of the decision by the patient is essential to determine whether shared decision-making has occurred; without closure by the patient, the physician may make decisions unilaterally. Traditionally, physicians are more vocal about closure than patients (e.g., ‘we will change your medicine’; ‘I want you to monitor your glucose’); patients’ verbalization of closure ensures their agreement.We calculated the total number of decision moments overall and by decision topic. The key outcome used in correlation analyses was the number of decision moments with ≥4 elements as defined above. We used Spearman rank correlations, a non-parametric test, to examine the association between number of decision moments with ≥4 elements and the CPX communication score for each case. Data analyses were performed using SPSS 17.0 (SPSS, Inc., Chicago).