The Effects of Physician Organization on the Disadoption of Low-Value Services: Evidence from PSA Testing and Mammography

Aditi P. Sen, PhD

Aditi P. Sen, PhD

Despite evidence that certain health care services are of low, or even no, value to patients, many of these services continue to be provided, raising costs for the health system and patients and potentially causing patients harm. Physicians are at the front line of providing care and yet, despite growing interest in reducing overutilization of care, physician “disadoption” of low-value technologies and services has received little attention. There is limited understanding of how information on clinical value diffuses across physician networks and what factors may promote – or hinder – disadoption of low-value care.

Two potential factors in physician decision-making around low-value care are their peers and the structure of the group in which they practice. In this paper, I examine the effects of peer behavior and group size on physician disadoption of low-value services in two settings: prostate cancer screening using the prostate-specific antigen (PSA) test following the 2012 guideline recommending against screening, and mammography for women under 50 following a change in the routine screening recommendation in 2009.

Using claims data from 2007-2013 from a major insurer in the Southeast Pennsylvania region, I find that physicians are significantly and positively affected by peers who practice in the same physical location while the behavior of peers with whom they have a relationship (through shared patients) but are not co-located does not have a significant impact. Further, local peer effects appear to peak in medium-sized physician groups of 11-30 physicians. Finally, in the case of PSA provision, positive peer effects in medium-sized groups are stronger following the 2012 recommendation relative to before the release, suggesting that physicians will be more likely to continue testing if their local peers continue testing, even following the recommendation against screening.

Together, these findings offer insight into how physicians make decisions about what services to provide and suggest that the organizational structure of physician group practices is likely to be a contributing factor to physician disadoption decisions. Given current policy trends towards new organizational arrangements for physicians, it is increasingly important to understand the dynamics of physician relationships in different settings and implications for health care quality and costs.