California Workers’ Comp IMR Volume Hit a Record High in 2016, But Outcomes Showed Little Change

OAKLAND, Calif.–(BUSINESS WIRE)–#CWCI–An analysis of the California workers’ comp independent medical review
(IMR) process used to resolve medical disputes finds that in 2016, IMR
physicians once again upheld about 90% of utilization review (UR)
physician’s modifications or denials of treatment, yet IMR volume
continued to grow, climbing 6.5% last year.

The California Workers’ Compensation Institute (CWCI) analysis is based
on a review of data from 477,045 IMR decision letters issued in 2014,
2015, and 2016 in response to applications submitted to the state after
a UR physician modified or denied a requested medical service. State
lawmakers who included IMR in the 2012 workers’ comp reforms expected
the process would reduce workers’ comp treatment disputes once doctors,
attorneys and other participants came to understand which services could
be approved because they meet evidence-based medicine standards. Three
years in, however, IMR volume is at a record high, as the Division of
Workers’ Compensation reports there were 10,477 more cases in 2016 than
in 2015.

The 2016 IMR outcomes data show that IMR physicians upheld the UR
doctor’s modification or denial of a requested service 91.2% of the
time, which was up from an 88.4% uphold rate in 2015 and matched the
rate noted in 2014. The mix of services reviewed by IMR physicians in
2016 showed little change from the two prior years, as prescription drug
requests (28.5% of which were for opioids) again accounted for nearly
half of all IMRs, with UR modifications or denials of pharmaceutical
requests upheld 92.5% of the time. Notably, requests for compounded
drugs (typically gels or creams) did represent a declining share of the
2016 prescription drug IMRs, as they fell from 8.0% of the 2015
determinations to 6.2% last year, which may have to do with their
consistently low IMR overturn rate (IMR physicians deemed them not
medically necessary 99% of the time in 2014, 2015, and 2016). Requests
for physical therapy, injections and durable medical equipment together
represented about 24% of the 2016 IMRs, while no other medical service
category accounted for more than 5% of the disputed requests. Among the
medical service categories, uphold rates in 2016 ranged from 78.9% for
evaluation and management services (primarily referrals for
consultations) to 93.6% for acupuncture.

As in the prior 2 years, the analysis found that most of the disputed
medical services that went through IMR in 2016 were requested by a small
number of physicians. The top 10% of physicians named in the 2016 IMR
decision letters (1,248 physicians) accounted for 85% of the disputed
service requests, while the top 1% (125 providers) accounted for 44%.
Significant geographic variation was again evident as well, as 32.8% of
the IMR decision letters were addressed to Los Angeles County recipients
even though the region only accounted for 23.6% of all workers’ comp
medical services in the state. IMR volume also was disproportionately
high in the Bay Area, which accounted for 20.1% of the IMR letters vs.
15.2% of the medical services; while less populated regions of the state
had a disproportionately small share of the IMRs, as did the Inland
Empire, Orange County and San Diego.

A complete analysis of the latest IMR results has been released in a
CWCI Spotlight Report, “Independent Medical Review Decisions: January
2014 Through December 2016.” Institute members and subscribers can
download the report and a summary Bulletin at,
while others can purchase a copy for $24 at


Bob Young, 510-251-9470