A study has shown that oncologists’ likelihood of adopting and using bevacizumab in the years after its approval was associated with whether their physician peers were early adopters.1
“As organizations seek to provide better care at lower costs, interventions that leverage physician ties may help to promote adoption of high-value use of new cancer treatments and deimplementation of low-value therapies,” the study researchers wrote.
In the analysis, researchers studied physicians and their patients at 51 randomly selected hospital referral regions in the United States. Participants included 44,012 fee-for-service Medicare beneficiaries aged 65 and older with colorectal, lung, breast, kidney, brain, or ovarian cancer. Patients were treated by 3261 oncologists between 2005 and 2010. Bevacizumab was initially approved in 2004.
The researchers established a model to assess association of bevacizumab use with rates of bevacizumab use in a physician’s community of connected physicians.
Unadjusted analyses showed that use of bevacizumab relative to all other chemotherapy in 2007 to 2010 was 10.0% among patients of physicians whose peers in their community had who the lowest rates of bevacizumab use in 2005 to 2006. The rate was 9.5% among physicians whose peers were in the middle tertile of bevacizumab use from 2005 to 2006. Bevacizumab use was highest at 13.6% among patients of physicians whose community bevacizumab use in 2005 to 2006 was in the highest tertile.
When the model estimated use of bevacizumab in 2007 to 2010 and incorporated physician, practice, and community random effects, it showed that among patients of physicians (829 physicians) whose peers had use of bevacizumab in 2005 to 2006 in the highest tertile, use of bevacizumab in 2007 to 2010 was statistically higher than among patients of physicians whose peers were in the lowest tertile of use in 2005 to 2006.
In an editorial, Damon Centola, PhD, of University of Pennsylvania, Philadelphia, said the study provided “valuable new insight.”
“These findings offer a crucial new insight into why there may be large regional variations in physicians’ use of new therapies,” Dr Centola wrote. “They suggest that patterns of regional variation may be due to social norms within physicians’ local medical communities that endorse some treatment practices and prohibit others.”
Disclosure: Dr Gray reported receiving personal and consulting fees from Grail.
- Keating NL, O’Malley AJ, Onnela JP, et al. Association of physician peer influence with subsequent physician adoption and use of bevacizumab [published online January 3, 2019]. JAMA Netw Open. doi: 10.1001/jamanetworkopen.2019.18586
- Centola D. Physician networks and the complex contagion of clinical treatment [published January 3, 2019]. JAMA Netw Open. doi: 10.1001/jamanetworkopen.2019.18585