The Role of Personality in Treatment-Related Outcome Preferences Among Pharmacy Students

Ernest H. Law, PharmD, PhD; Ruixuan Jiang, PharmD; Anika Kaczynski, MS; Axel Mühlbacher, PhD; A. Simon Pickard, PhD


Am J Pharm Educ. 2019;83(7) 

In This Article

Abstract and Introduction


Objective. To examine whether personality traits, particularly conscientiousness and agreeableness, were associated with systematic differences in health outcome preferences in cancer treatment scenarios among second-year Doctor of Pharmacy students.

Methods. An online survey that quantified outcome preferences using profile best-worst scaling tasks was administered to pharmacy students (n=185). The Big Five personality inventory was used to categorize respondents into tertile-based levels of each trait. Treatment-related health outcomes were described using the EQ-5D-Y system and framed with hypothetical cancer treatment scenarios. Preferences were obtained using count analysis for each treatment-related outcome, and differences based on the level of trait were tested using analysis of variance. Logistic regression was used to test for significant associations between higher levels of a trait and choosing dead over a severe health state.

Results. Higher conscientiousness was associated with students who had an approximately 20% more positive preference for "no problems" in the Usual Activities and Pain/Discomfort attributes, as well as a 19% more negative preference for "a lot of problems" in the Pain/Discomfort attribute. No differences in treatment preferences were observed across agreeableness tertiles. Higher levels of personality traits were not significantly associated with choosing death over being in moderate health.

Conclusion. Conscientiousness appears to be a factor in treatment-related outcome preferences among pharmacy students. Individuals with higher levels of conscientiousness may be more likely to recommend treatments that are less likely to cause pain or discomfort and negatively impact a patient's usual activities.


The process of shared decision-making is an important vehicle for patient-centered care. Shared decision-making mandates sharing of knowledge, experiences, and values between the clinician and the patient.[1] If a clinician is to act as an advocate for the patient, understanding how a clinician values treatment-related outcomes is necessary to better characterize the patient-clinician dynamic in shared decision-making.

The shared decision-making process may be affected by the personalities of the parties involved. Two personality traits, conscientiousness and agreeableness, may be particularly important traits in clinicians. Both traits are part of the Big Five framework, a psychological model that represents personality traits within five broad domains: extraversion, agreeableness, conscientiousness, emotional stability, and openness to experience.[2] Conceptually, conscientiousness is defined as the ability to control impulses to facilitate task- and goal-directed behavior; agreeableness is described as altruism, cooperation, and willingness to exhibit warmth and kindness.[3] In principle, having higher levels of conscientiousness and agreeableness may enable a clinician to better accommodate the perspective of the patient and potentially empathize with the patient's emotional mindset. Previous studies have shown that in patients, conscientiousness and agreeableness traits were associated with differences in patients' health preferences as well as increased engagement with clinicians in shared decision-making.[4,5] Therefore, these two personality traits are considered important characteristics for a clinician to have to be able to make health care decisions that are in the best interest of the patient. However, this literature is in its infancy. The extent to which the personality traits of practicing and future pharmacists, particularly their conscientiousness and agreeableness, are relevant to their ability to select among health outcomes in life-threatening conditions where the input of an experienced health care professional is highly valued is unclear.

One method to quantify the value that respondents place on different health outcomes is to use choice-based preference elicitation techniques such as discrete choice experiment or best-worst scaling. Initially developed for market research, the discrete choice experiment is an ordinal-based approach that gathers information on preferences by asking individuals to choose their preferred products or health states.[6,7] The best-worst scaling method is an extension to the discrete choice experiment. The case 2 (or profile based) best-worst scaling method aims to elicit preferences for a set of attributes, their associated levels or alternatives by estimating the relative importance on a common scale.[8–10] Best-worst scaling assumes that respondents are capable of making judgments regarding the best and the worst item out of three or more characteristics in a decision or choice.[11,12] Ordinal-based methods have significant advantages over traditional methods of assessing preferences, such as Likert-type scale items in simple surveys. Although Likert-type questions ask respondents about the importance of outcomes (eg, 1=not important, 5=extremely important), they do not provide information on trade-offs required in real-life clinical decisions. Stated preference techniques attempt to simulate actual decision making by requiring respondents to assess trade-offs in a realistic, albeit hypothetical, decision context.[10]

Given the conceptual basis and support in the literature for the association between conscientiousness and agreeableness with shared decision-making, we sought to examine the relationship between these two traits and health outcome preferences in future pharmacists. Specifically, this study aims to compare the importance assigned to cancer treatment outcomes by levels of conscientiousness and agreeableness; and to examine whether the perception of death as an outcome choice systematically differs by levels of conscientiousness and agreeableness among second-year pharmacy students.