However, longer-term dispensing of opioids was more prevalent in Louisiana and several other states in the study period of 2013 through 2015, according to the study. Moreover, WCRI continued to find that fewer-than-expected injured workers who received opioids on a longer-term basis had certain services recommended by treatment guidelines for chronic opioid management.

“Long-term opioid therapy for chronic non-cancer pain is a controversial topic, and there is little evidence about the effectiveness of such treatment on functional recovery or return to work,” Wang writes. “Unnecessary opioid prescriptions may lead to opioid addiction, overdose, and diversion, which is a top priority public health topic in the United States. The public concern is also shared by the workers’ compensation community.”

Key findings from the study include:

• The frequency of claims that received opioids on a longer-term basis decreased more than 4 percentage points in Kentucky and New York. The same measure decreased 2 to 3 percentage points in several other states (Kansas, Massachusetts, Michigan, Minnesota, and Tennessee). Noticeable decreases in the longer-term dispensing of opioids were also seen in several other states, including California, Florida, and Texas, with reductions of 1 to 2 percentage points.

• Among claims with injuries in 2013 that were observed over a two-year time period ending March 2015, longer-term dispensing of opioids was most prevalent in Louisiana: 1 in 6 injured workers with opioid prescriptions were identified as receiving longer-term opioids. Compared with most study states, the number was also higher in California, Georgia, North Carolina, Pennsylvania, South Carolina, and Texas. By contrast, about 1 in 25 injured workers with opioid prescriptions received them on a longer-term basis in Indiana, Kansas, Missouri, Nevada, New Jersey, and Wisconsin.

• The study continued to find that fewer-than-expected injured workers who received opioids on a longer-term basis had certain services (i.e., drug testing, psychological evaluation and treatment, etc.) recommended by treatment guidelines for chronic opioid management. For example, in 19 out of 26 states, less than 10 percent of injured workers with longer-term opioids received psychological evaluations.

• This study uses data comprising over 400,000 nonsurgical workers’ compensation claims with more than seven days of lost time, and over 2 million prescriptions are associated with these claims from 26 states. These claims had injuries in 2010 and 2013 and received on average up to 24 months of medical treatment. The sample of claims in the study represents 36 percent t- 69 percent of workers’ compensation claims in each state.

• The 26 states in the study are Arkansas, California, Connecticut, Florida, Georgia, Illinois, Indiana, Iowa, Kansas, Kentucky, Louisiana, Maryland, Massachusetts, Michigan, Minnesota, Missouri, Nevada, New Jersey, New York, North Carolina, Pennsylvania, South Carolina, Tennessee, Texas, Virginia, and Wisconsin.