No conflict of interest was declared.
Agreement and validity of pharmacy data versus self-report for use of osteoporosis medications among chronic glucocorticoid users†
Article first published online: 23 FEB 2006
Copyright © 2006 John Wiley & Sons, Ltd.
Pharmacoepidemiology and Drug Safety
Volume 15, Issue 10, pages 710–718, October 2006
How to Cite
Curtis, J. R., Westfall, A. O., Allison, J., Freeman, A., Kovac, S. H. and Saag, K. G. (2006), Agreement and validity of pharmacy data versus self-report for use of osteoporosis medications among chronic glucocorticoid users. Pharmacoepidem. Drug Safe., 15: 710–718. doi: 10.1002/pds.1226
- Issue published online: 21 SEP 2006
- Article first published online: 23 FEB 2006
- Manuscript Accepted: 7 DEC 2005
- Manuscript Revised: 28 NOV 2005
- Manuscript Received: 15 AUG 2005
- Agency for Healthcare Research and Quality. Grant Number: HS10389
- National Institute for Arthritis and Musculoskeletal and Skin Diseases. Grant Number: P60 AR48095
- National Institutes of Health. Grant Number: T32 AR47512-03
- self report;
- sensitivity and specificity;
- diagnostic tests;
Pharmacy and linked claims databases are commonly used to determine medication receipt as a measure of quality of care. However, these data sources have not been previously compared with self-reported data for receipt of medications used for glucocorticoid-induced osteoporosis (GIOP).
Using databases from a national managed care organization (MCO), we identified 6282 chronic glucocorticoid users (60+ days in 18 months). We compared self-reported current use of alendronate, risedronate, calcitonin, and raloxifene (reference standard) to different intervals of preceding pharmacy data to determine agreement, sensitivity, specificity, and positive and negative predictive values of the pharmacy data.
Survey respondents (n = 2363) were mean ± SD age 53 ± 14 years old, 70% women, and 78% Caucasian. Agreement between self-reported and pharmacy data ranged from Kappa = 0.64 (95%CI 0.53–0.75) (calcitonin) to 0.80 (0.76–0.84) (alendronate). The positive predictive value of a filled prescription in the pharmacy database in the prior 6 months exceeded 90% compared to the reference standard of self-reported current bisphosphonate use. However, the 6-month interval of pharmacy data failed to capture >25% of self-reported current bisphosphonate users. The optimal interval of pharmacy data to distinguish between current and past bisphosphonate users was 120–180 days.
Among chronic glucocorticoid users enrolled in managed care, underreporting of current osteoporosis medication use was uncommon, and agreement between self-report and pharmacy data was high. Use of pharmacy data alone is unlikely to underestimate quality of osteoporosis care, but different intervals of pharmacy data have important implications on the ability to identify current users of osteoporosis medications. Copyright © 2006 John Wiley & Sons, Ltd.