Background: Implementation of the Health Insurance Portability and Accountability Act (HIPAA) Privacy Rule has the potential to affect data collection in outcomes research.
Methods: To examine the extent to which data collection may be affected by the HIPAA Privacy Rule, we used a quasi-experimental pretest-posttest study design to assess participation rates with informed consent in 2 cohorts of patients eligible for the University of Michigan Acute Coronary Syndrome registry. The pre-HIPAA period included telephone interviews conducted at 6 months that sought verbal informed consent from patients. In the post-HIPAA period, informed consent forms were mailed to ask for permission to call to conduct a telephone interview. The primary outcome measure was the percentage of patients who provided consent. Incremental costs associated with the post-HIPAA period were also assessed.
Results: The pre-HIPAA period included 1221 consecutive patients with acute coronary syndrome, and the post-HIPAA period included 967 patients. Consent for follow-up declined from 96.4% in the pre-HIPAA period to 34.0% in the post-HIPAA period (P<.01). In general, patients who returned written consent forms during the post-HIPAA period were older, were more likely to be married, and had lower mortality rates at 6 months. Incremental costs for complying with the HIPAA Privacy Rule were $8704.50 for the first year and $4558.50 annually thereafter.
Conclusions: The HIPAA Privacy Rule significantly decreases the number of patients available for outcomes research and introduces selection bias in data collection for patient registries.