cwci logo
Sign In

Our online store is currently undergoing maintenance to improve your experience. If you have any questions, please contact us at info@cwci.org.

Communications / news / press release

Press Release

California WC IMR Volume Fell Slightly in 2017, But Outcomes Held Steady

March 14, 2018

Oakland – New data on the Independent Medical Review (IMR) process used to resolve California workers’ comp medical disputes show that IMR volume dipped for the first time ever in 2017,  but the outcomes were unchanged as IMR physicians again upheld 91.2% of modified or denied medical service requests that they reviewed. 

     The California Workers’ Compensation Institute (CWCI) analysis is based on a review of 648,450 IMR decision letters issued from 2014 through 2017 in response to applications submitted to the state after a UR physician modified or denied a requested medical service.  In adopting IMR in 2012 state lawmakers anticipated that once doctors, attorneys and others came to know which services could be approved as meeting evidence-based medicine standards the process would reduce treatment disputes, but 2017 marks the first time in the five years since its inception that IMR volume has declined, as the Division of Workers’ Compensation data show 3,808 fewer cases in 2017 than in 2016, which translates to a relatively modest 2.2% decline.

     A review of the 2017 IMR results shows that IMR physicians upheld the Utilization Review (UR) doctors’ modifications or denials of  requested services 91.2% of the time, which was exactly the same uphold rate as in 2014 and in 2016.  The mix of service requests reviewed by IMR physicians in 2017 showed only minor changes from 2016, as prescription drug requests (29.1% of which were for opioids) again accounted for the largest share of the IMRs (46.0% vs. 47.9% in 2016), with UR determinations on pharmaceutical requests upheld 92.0% of the time.  Aside from the opioid requests, requests for musculoskeletal drugs, dermatologicals, and anti-inflammatory drugs topped the list of pharmaceutical IMRs, while compound drug requests fell from 6.5% of the prescription drug IMRs in 2016 to 4.2% in 2017, the biggest decline of any prescription drug category, which may be linked to the fact that IMR physicians have consistently deemed them not medically necessary in 99% of the cases.  Similar results were noted for most of the dermatological requests, with IMR physicians upholding modifications or denials of requests for topical local anesthetics, manufactured topicals, and topical corticosteroids 97% to 98% of the time.  Among other medical service categories, physical therapy, injections, and durable medical equipment once again combined for about a quarter of the IMRs in 2017, but no other medical service category represented more than 5% of the disputed requests.  Among all medical service categories, requests for evaluation and management services (primarily referrals for consultations) again had the best chance of being overturned by IMR, (an IMR uphold rate of 79.2%), while modifications or denials of physical therapy and acupuncture were the least likely to be overturned, with IMR upheld 94.0% of the time for both categories.

     As in prior years, most of the disputed requests that went through IMR in 2017 came from a small number of physicians, with the top 10% of physicians who were named in decision letters (1,150 physicians) accounting for 85% of the disputed requests, while the top 1% (115 providers) accounting for 45%.  Los Angeles and Bay Area continue to represent a disproportionately high share of the IMR cases relative to their share of paid medical services, while the more rural areas have a disproportionately low share of the IMR cases.   

     CWCI has released a more detailed analysis of the 2017 IMR results in a Research Update, “Independent Medical Review Decisions: January 2014 Through December 2017.”  Institute members and subscribers can download the report and a Bulletin at www.cwci.org, while others can buy a copy for $24 at Store.

Explore More News

Independent Medical Review Trends and Outcomes, 2015-2025

Read More

CWCI: COVID-19 Drove Recent Volatility in California Work Injury and Illness Trends

Read More

Emerging Drug Classes in California Workers' Comp: Psychotherapeutic & Neurological Drugs

Read More

Registration Now Open for CWCI's 62nd Annual Meeting

Read More

California Public Self-Insured Workers' Comp Claims Fell Last Year, But Losses Hit New Highs

Read More

CWCI: New California WC Medical Mileage Rate For Travel On or After January 1, 2026

Read More

DIR Announces 2026 California Workers' Comp User Funding Assessment Rates

Read More

SAWW Increase to Require A California Workers Comp Benefit Bump in 2025

Read More

CWCI Report Examines Functional Restoration Programs in California Workers' Comp

Read More

Sara Widener-Brightwell Promoted to CWCI Executive Vice-President and General Counsel

Read More

We’re in the process of rolling out updates and improvements.

This feature will be restored shortly.

For assistance, please email us at