Abstracts

Rationale: Diaries are frequently used in clinical research to assess patient experiences and inform interventions. It is commonly believed that electronic diaries (e-diaries) increase adherence over paper diaries. We examined diary adherence across three studies with varying data collection and transmission formats focusing on two endpoints: subject retention over an 8 week study period; and percent of missing diary days among subjects that completed the 8 weeks.Methods: We examined study retention at 8 weeks as well as daily diary adherence across studies utilizing three formats: 1) A paper diary study with monthly return by mail; 2) an e-diary with a Palm-based Patient Reporting Outcome (ePRO) program and manual data upload via telephone transmission to a central server and 3) data collected during the 8 week baseline phase of a smartphone-based e-diary clinical trial (Stress Management Intervention for Living with Epilepsy-SMILE) with instantaeous cell transmission upload. The paper diary was completed once daily in the evening while the electronic diaries were each completed twice daily. As the diaries were kept for different lengths of time, we examined adherence during the first 8 weeks of diary maintenance (56 consecutive days). Information collected in the diaries included the occurrence, time and characteristics of all seizures, as well as medication compliance, hours of sleep, stress and anxiety measurements, menstrual status, and seizure self-prediction. The total number of data items collected in each questionnaire is indicated (Table 1). Subjects in all three studies were at least 18 years old, had localization-related epilepsy, and were capable of independently maintaining the diary.Results: Of patients enrolled in each study, retention rate was 62% (paper diary, N=133), 91% (Palm-based e-diary, N=22) and 90% (smartphone e-diary, N=39) (Table 1). Among subjects who completed the 8 weeks, the paper diary had the highest daily adherence (98%), while the electronic studies had somewhat lower daily adherence. Specifically, adherence in the palm pilot study was 93% for AM entries and 92% for PM entries, while adherence in the smartphone study was 94% for both AM and PM entries (Table 1). Of note, the number of data items collected was higher for the e-diaries than the paper diary (Table 1).Conclusions: Daily diary maintenance for epilepsy studies is feasible and adherence is high. An electronic diary format improves retention over a paper diary format. While subject burden was higher in the e-diary studies given twice daily data collection and a larger number of data items collected in each questionnaire, overall adherence was extremely robust across all diary formats.