California Workers’ Comp Independent Medical Review Volume Fell in First Half of 2022

October 3, 2022

After hitting a record low in 2021, the number of independent medical reviews used to resolve California workers’ comp medical disputes continued to decline in the first half of 2022 according to the California Workers’ Compensation Institute.

California law requires workers’ comp claims administrators to have a Utilization Review program to ensure treatment provided to injured workers is supported by clinical evidence outlined in the state’s Medical Treatment Utilization Schedule.

Most treatment requests are approved by UR, but in 2012 state lawmakers adopted IMR to allow injured workers to obtain an independent medical opinion on requests that UR physicians deny or modify. IMR took effect for all claims in July 2013, and CWCI began monitoring IMR activity in 2014.

CWCI’s latest review shows that 62,859 IMR decision letters were issued in the first half of this year in response to applications submitted to the state, down 7.6% from 68,039 letters issued in the first six months of 2021, while the latest full-year count shows 133,494 letters issued in 2021, down 2.4% from 136,738 letters in 2020. That’s down 27.7% from the all-time high of 184,735 letters in 2018, according to the institute.

IMR letters often include decisions on multiple medical service requests, and as the volume of letters has declined in recent years, the number of service decisions has dropped as well. In 2019, the last year prior to the pandemic, IMR physicians issued medical necessity decisions on 261,708 primary service requests, but by 2020 that had fallen 17.5% to 215,788 decisions, and in 2021 it continued down. The latest data show that in the first half of 2022 IMR physicians issued 97,649 decisions on primary medical service requests.

The distribution of IMRs by type of medical service request show that since peaking in 2018, IMR letter counts have declined across all medical service categories, but most of the overall decline in IMR can be traced to the sharp decline in prescription drug disputes following the Chronic Pain and Opioid Guidelines into the MTUS in late 2017.

Disputes over prescription drug requests dropped from 47.3% of all IMRs in 2017 to 34.9% of all IMRs in 2021, with the latest data showing prescription drug disputes were down to 33.9% of the IMR disputes in the first half of this year.

CWCI has published additional data and analyses on the IMR data through June 2022 in a bulletin, which Institute members and subscribers will at the institute’s website,