Background: The feasibility and accuracy of obtaining patient reported outcomes electronically, particularly from elderly subjects, has been questioned. OBJECTIVES: To pilot the use of a telephone-based Interactive Voice Response Data Entry System (IVRS) by elderly caregivers of patients with Alzheimer's Disease. METHODS: Caregivers were trained by nurses to record patient and caregiver health care utilization data into a 30-day diary and to enter these data using IVRS. The system was accessed via a toll-free telephone number using a unique subject identifier. Caregivers had 15 minutes to read detailed training notes in the waiting room. Feasibility and accuracy parameters assessed were time to train, time to enter the data and accuracy of hypothetical diary data entry. RESULTS: Time to train the caregiver (60% women, 52 to 80+ years old) on both the use of the diary and IVRS data entry ranged from 36 to 48 minutes. Thirty days of hypothetical diary data provided to the patient for the exercise were entered via IVRS in 8 to 12 minutes per subject. No significant difficulties were observed with any caregiver and only one data point by one caregiver was incorrectly entered. IVRS features such as question repeat, invalid answer prompt, and automatic re-entry to last question answered if entry was interrupted all worked well. Caregivers expressed their willingness to use the diary daily and to enter data every 30 days over the planned 18-month study. All study nurses expressed their preference for this design versus a traditional nurse interview, paper-based design, primarily due to decreased site burden in relation to data collection. CONCLUSION: The use of a prospective diary and IVRS data entry by the elderly is feasible and offers the possibility to collect detailed prospective health economic data with a minimum of burden to site study staff.