FACTORS AFFECTING PHYSICIANS' INTENTIONS TO COMMUNICATE PERSONALIZED PROGNOSTIC INFORMATION TO CANCER PATIENTS AT THE END OF LIFE: AN EXPERIMENTAL VIGNETTE STUDY

Purpose:

To explore the effects of personalized prognostic information on physicians’ intentions to communicate prognosis to cancer patients at the end of life, and to identify situational and physician characteristics that moderate these effects.

Method:

A factorial experiment was conducted among a sample of 93 Family Medicine physicians affiliated with residency training programs in northern New England.  Participants were presented with a hypothetical case vignette depicting an acutely ill, end-stage gastric cancer patient asking about his prognosis.  Participants’ intentions to communicate prognostic information were assessed both before and after provision of an evidence-based, personalized prognostic estimate (78% mortality risk) from a hypothetical clinical prediction model.  The emotional state of the hypothetical patient (distressed vs. non-distressed) and ambiguity in the prognostic estimate (ambiguous risk range vs. unambiguous point estimate) were varied between subjects.  Other potential determinants of prognostic communication were measured:  1) perceived patient distress, 2) perceived credibility of prognostic models, 3) individual differences in physicians’ objective and subjective numeracy, and 4) individual differences in physicians’ aversion to ambiguity.  General linear models were used to assess the effects of personalized prognostic information on the change in prognostic communication intentions, and to identify factors that moderate these effects and influence intentions to communicate available prognostic information.

Result:

Provision of personalized prognostic information significantly increased prognostic communication intentions (p<.001, η²=.39).  There were no significant effects of the experimental factors (patient distress, prognostic ambiguity) on change in communication intentions.  However, several variables moderated the effects of prognostic information.  Greater change in prognostic communication intentions following provision of prognostic information was associated with lower perceptions of patient distress (p=.01, η²_p=.08), greater objective numeracy (p=.03, η²_p=.06), greater perceived credibility of prognostic models (p=.056, η²_p=.045), and lower ambiguity aversion (p=.07, η²_p=.04).  Similarly, greater intentions to communicate personalized prognostic information were associated with greater subjective numeracy (β=.19, p=.005, η²=.10), lower ambiguity aversion (β=-.08, p=.008, η²=.08), and greater perceived credibility of prognostic models (β=.49, p=.02, η²=.06).

Conclusion:

The provision of personalized prognostic information increases physicians’ intentions to communicate prognosis to a hypothetical cancer patient at the end of life, and several situational and physician characteristics moderate this effect.  More research is needed to confirm these findings in actual clinical practice, and to identify and reduce barriers to prognostic communication in end-of-life care.