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CWCI Takes An Updated Look At California Workers' Comp Medical Dispute Resolution

Oakland, CA – A new California Workers’ Compensation Institute (CWCI) study on the Independent Medical Review (IMR) process used to resolve California workers’ comp medical disputes shows that after dipping for the first time ever in 2017, the number of IMR decision letters rose to an all-time high in 2018, though once again in about 9 out of 10 cases IMR physicians upheld the modified or denied medical service requests that they reviewed. 

The CWCI study is based on a review of nearly 830,000 IMR decision letters issued from 2014 through 2018 in response to applications submitted to the state after a Utilization Review (UR) physician modified or denied a workers’ compensation medical service request.  As in prior studies, the researchers used data from the letters to:

• identify changes in the volume, timeliness, and regional distribution of IMRs;
• determine the number, mix, and uphold rates for the medical service requests that were reviewed;
• examine the distribution and outcomes of pharmaceutical IMRs by drug category; and
• measure the percentage of 2018 IMRs associated with high-volume medical providers.

In addition, CWCI added three new elements to the research: determining the concentration of IMR submissions by high-volume law firms; calculating the distribution of pharmaceutical vs. non-pharmaceutical IMRs by claim age; and estimating the percentage of IMRs submitted after a UR physician approved the service at a lesser quantity than requested in order to comply with the Medical Treatment Utilization Schedule guidelines, which provide the clinical rationale for workers’ compensation treatment in California.

Although state lawmakers expected IMR volume to diminish over time, the number of IMR determination letters has increased steadily since the process was introduced in 2014 -- the only exception being a 2.2% decline in 2017.  The latest figures show the number of IMR letters climbed to a record 184,733 in 2018, up 7.3% from 2017 and up 28.4% since 2014.  The biggest increase in letter volume last year was in the Bay Area, which had 4,500 more letters in 2018 than in 2017, while San Diego had the biggest percentage increase (18.3%).  As has been the case since IMR was implemented, a small number of physicians continue to drive much of the IMR activity, with the top 1% of requesting physicians (122 doctors) accounting for 44.2% of the disputed service requests that underwent IMR in 2018; and the top 10 individual physicians alone accounting for 9.5% of the disputed requests.  Notably, 95% of the letters were in response to applications from injured worker representatives – almost all of them attorneys.  The authors tallied 541 law firms that were named in more than 50 IMR determination letters in 2018, with the top 10 firms alone accounting for 15% of all IMR volume; the top 25 accounting for 25%; and the top 50 accounting for 35.4%.      

IMR outcomes were fairly stable as IMR physicians upheld the UR doctors’ modification or denial of services nearly 90% of the time, with uphold rates ranging from 75.8% for evaluation/management services to 92.7% for acupuncture.  The mix of services reviewed by IMR physicians in 2018 showed prescription drug requests continued to top the list, accounting for 46.3% of the IMRs (and 32.2% of those were for opioids), though musculoskeletal drugs and anticonvulsants also accounted for a growing share of the pharmaceutical IMRs. 

CWCI has issued its latest IMR analysis in a Research Update Report, “Independent Medical Review Decisions: January 2014 Through December 2018,” which is posted under the Research tab at www.cwci.org