Feasibility and accuracy of a postcard diary system for tracking healthcare utilization of community-dwelling older persons.

OBJECTIVE

To test the feasibility of and to validate a self-report weekly postcard diary of health care utilization.

DESIGN

Case-series and validation study.

SETTING

Community-based sample of fee-for-service and health maintenance organization (HMO) patients.

PARTICIPANTS

A convenience sample of 24 community-dwelling older persons who had failed a self-administered screen and were eligible for a study of outpatient comprehensive geriatric assessment consultation.

MEASUREMENTS

Subjects completed and mailed in a weekly postcard diary documenting medical, counseling, or rehabilitation therapy visits. If a subject did not respond within 10 days after the end of the week, a telephone call was placed to gather the information. For a subset of 10 subjects who were HMO enrollees, all records were reviewed to determine accuracy of the postcard diaries.

RESULTS

Of the 24 subjects enrolled, one HMO enrollee dropped out following hip surgery after 4 weeks of completing diaries. The remaining 23 subjects (96% of total entered) provided complete information for 12 weeks. Telephone follow-up to either obtain or clarify utilization information was required for 22% of subjects. For the subset of 10 HMO subjects, seven underreporting, two overreporting, and one incorrect day errors were detected-a total of 10 errors representing 9% of diaries and 1.3% of patient-days. Kappa as a measure of agreement between the two methods (self-report and chart review) was 0.82 (P < .0001). Compared with chart review, the diary report was 75.0% sensitive and 99.8% specific. Positive and negative predictive values were 91.3% and 99.2%, respectively.

CONCLUSION

These findings suggest that a postcard diary system with telephone follow-up is both a feasible and reasonably accurate method of tracking health care utilization by community-dwelling older persons, although a small percentage will be unable to adhere to this method.