Subject preferences in randomization assignment: comparison between randomized assignment preference, perceived intervention value, and personality type [presentation] Presentation uri icon


  • Background/Aims: The Journey for Control of Diabetes: the IDEA Study, a randomized clinical study, evaluated the effectiveness of an interactive, group-based learning experience using the U.S. Diabetes Conversation Map™ program. This abstract explores the degree to which subject preference for randomization assignment was related to perceived value of the diabetes education received, demographic variables, and personality type. Methods: Subjects (n=623) with uncontrolled Type 2 diabetes (A1c = 7) were enrolled in the 2-site study (Albuquerque, NM, and Minneapolis, MN) and randomized to either group education (GE), individual education (IE), or usual care (UC). All 623 subjects completed a baseline survey which included the five personality types measured by the Ten Item Personality Inventory (extraversion, conscientiousness, emotional stability, agreeableness, or openness to new experiences). A total of 526 subjects completed the 12-month final survey which included subject preference for randomized assignment and perceived value of the education received. Results: Of GE and IE treatment subjects, 53.3% (112/210) and 50.8% (102/201) respectively, reported being placed in the group they preferred compared to 3.5% (4/115) of those randomized to UC (p<.0001). In Albuquerque, 48.9% (113/231) of subjects reported being placed in the study arm they preferred compared to 35.6% (105/295) in Minneapolis (p=.0032). There were 38.4% (99/258) men who reported being placed in the study arm they preferred compared to 44.4% (119/268) women; additionally, 36.8% (95/258) of males had no preference compared to 25.8% (69/268) females (p=.0230). Subjects randomized to their preferred study arm (excluding those in UC receiving no education), 91.3% (189/207) reported their diabetes education as ‘valuable’ or ‘very valuable’ compared to 71.0% (44/62) subjects not in their preferred study arm, or 81.6% (84/103) of those with no preference for assignment (p<.0001). There were no significant differences in study arm preference or perceived education value related to any of the five personality types. Conclusions: Subject preference for random assignment is a measure which should be monitored as it has potential implications for clinical practice to affect attitudes, perceptions of satisfaction, and clinical outcomes of the intervention. Further analyses will be conducted to determine if subject preference affected clinical and behavioral outcomes.