Measuring informed decision making about prostate cancer screening in primary care.

PURPOSE: To measure the extent of informed decision making (IDM) about prostate cancer screening in physician-patient encounters, describe the coding process, and assess the reliability of the IDM measure. METHODS: Audiorecoded encounters of 146 older adult men and their primary care physicians were obtained in a randomized controlled trial of mediated decision support related to prostate cancer screening. Each encounter was dual coded for the presence or absence of 9 elements that reflect several important dimensions of IDM, such as information sharing, patient empowerment, and engaging patients in preference clarification. An IDM-9 score (range = 0-9) was determined for each encounter by summing the number of elements that were coded as present. Estimates of coding reliability and internal consistency were calculated. RESULTS: Male patients tended to be white (59%), married (70%), and between the ages of 50 and 59 (70%). Physicians tended to be white (90%), male (74%), and have more than 10 years of practice experience (74%). IDM-9 scores ranged from 0 to 7.5 (mean [SD], 2.7 [2.1]). Reliability (0.90) and internal consistency (0.81) of the IDM-9 were both high. The IDM dimension observed most frequently was information sharing (74%), whereas the dimension least frequently observed was engagement in preference clarification (3.4%). CONCLUSIONS: In physician-patient encounters, the level of IDM concerning prostate cancer screening was low. The use of a dual-coding approach with audiorecorded encounters produced a measure of IDM that was reliable and internally consistent.