California's workers' compensation (WC) program provides medical care and indemnity (e.g., wage-replacement) benefits to workers who suffer on-the-job injuries and illnesses. Injured workers are entitled to receive all medical care reasonably required to cure or relieve the effects of their injuries with no deductibles or copayments. An estimated 16 million workers use WC insurance annually in California; this use covers claims filed for workplace-related injuries and benefits and ranges from minor medical treatment to catastrophic traumatic brain injuries and spinal cord injuries (National Academy of Social Insurance, 2017).
High rates of growth in medical care expenditures resulted in a series of reform efforts to control medical treatment expenses for injured workers and to improve program efficiency. To address these recent fluctuations in medical care expenditures and the increase in medical cost containment expenses and medical-legal costs, California Senate Bill (SB) 863 was passed in 2012, with various provisions becoming effective in 2013 and 2014. Collectively, the intent of the SB 863 provisions was to improve the quality, efficiency, and timeliness of medical care provided to injured workers by changing fee schedules, dispute-resolution processes, accountability, and oversight. The policy changes included a new resource-based, relative-value scale fee schedule for practitioner services; a major restructuring of the medical-necessity determination process; and monitoring of medical provider networks (MPNs).
Many of these recent policy changes might have affected access to care for injured workers, including changes in the availability of appropriate providers and services; timeliness of care; and other inadvertent changes in cultural, social, or other barriers that could prevent care. Specifically, changes to the fee schedule and medical treatment dispute processes might have affected the decisions of some providers in terms of their interaction with WC patients and the WC system. Although this work is not an evaluation study of the direct impact of these changes, it is important to assess the various dimensions of access to care in the evolving policy environment to ensure that injured workers have adequate access to needed medical care and the opportunity to achieve better health outcomes.
The Division of Workers' Compensation (DWC) is mandated by California Labor Code Section 5307.2 (2009) to support an annual assessment of whether injured workers have adequate access to quality care; this assessment is conducted by an independent contractor and authorizes the administrative director of DWC to make appropriate adjustments in fee-schedule amounts if the administrative director determines that there is inadequate access to care.
Access to care is an important domain to monitor, especially among vulnerable populations, as patients with better access to care systems are more likely to receive comprehensive, higher-quality care and are therefore more likely to experience better outcomes (Kominski et al., 2006; Kominski et al., 2008).
The term access, as it applies to obtaining health care services, has been defined by the Institute of Medicine as the timely use of personal health services to achieve the best-possible health outcomes and is often measured in medical data by utilization of health services and health outcomes (Institute of Medicine, 1993). Measuring access using health outcome indicators can be challenging, however, because health outcomes are often the result of a multitude of factors and may not be directly correlated with medical care or utilization of health services. More-recent definitions view access as the opportunity that consumers or communities have to consume health goods and services, or the ease with which they consume these goods and services, in proportion to their needs (Haddad and Mohindra, 2002; Peters et al., 2008). These definitions regard access as including actual use of services and emphasize characteristics of users and services in evaluating access. Use of health care services as an access indicator also has limitations: The distribution of health care utilization varies across populations and is not an exact reflection of the health care needs of those populations.
Because access to health care is one of the key dimensions of health care quality, there has been significant interest in refining measurements to improve construct validity (Donabedian, 1966; Berenson, Pronovost, and Krumholz, 2013); in fact, the Agency for Healthcare Quality and Research has devoted significant resources to better measurement (e.g., through the National Quality Measures Clearinghouse). Measures are often differentiated across three key elements: structures, processes, and outcomes (Donabedian, 1966). Structural measures are those we might expect the California Department of Industrial Relations (DIR) and DWC to have the most influence in affecting for workers with workplace injuries, since these measures typically have rules and regulations imposed by payers systemwide. Process measures reflect aspects of the health care experience (e.g., receipt of guideline-concordant care, aspects of obtaining an appointment and wait times, referral patterns). Finally, outcome measures reflect whether appropriate care was received and, ultimately, whether health was improved. There are other measures that are correlated with the institutional structures, processes, and outcomes that are often used in the literature as proxies. Proxy measures—such as physician supply, physician willingness to participate, timeliness to care or waiting times, and geographic proximity—are often used to gauge resource availability, an important indicator of access. Other proxy measures—such as utilization of services, specialist-referral patterns, provider type, care setting, purpose of encounter, and the frequency or continuity of care—can be used to assess access to adequate or appropriate care. However, just focusing on any one element of access can be misleading. For example, examining health outcomes can be useful in illuminating obstacles to obtaining care, with the caveat that there are other factors—such as adherence, treatment effectiveness, and health behaviors, as well as unobservable measures—that are correlated with both health outcomes and access to care. In other words, statistical associations between health outcomes should be viewed as correlational and not necessarily causal.
The key objective of this study is to describe access to medical care among injured workers in the state of California, as mandated by Labor Code Section 5307.2. This work builds on earlier California WC access reports sponsored by the state, which used surveys to examine medical care provided to injured workers and analyzed medical billing data. This study analyzes administrative and medical service bill data from the Workers' Compensation Information System (WCIS) to examine changes over time for measures related to access to care for injured workers. WCIS is the reporting tool used by the DIR to collect comprehensive information from WC claims administrators about initial reports of injuries and all medical billing related to WC care.
In examining trends over time, we aim to highlight potential access-to-care barriers in the WC system and to understand whether changes in the WC system may be increasing access for injured workers. Although we discuss potential explanations for the trends observed here, our analyses should be considered descriptive, since we are not conducting causal analysis.
Medical bill and administrative data offer an important but limited window into access to care for injured workers. These data can be used to calculate a range of measures related to access to care for injured workers, such as the number of providers who treat injured workers, the time from injury to treatment and between different services, and the fraction of injured workers who receive appropriate follow-up care after specialist visits. Other important aspects of access—such as patient satisfaction with the availability of necessary care or provider perceptions of the WC system—are impossible to gauge in medical bill and administrative data.
In this annual access study, the RAND Corporation team explores different measures of access that can be constructed from the WCIS medical claims data. This year 1 study establishes a baseline assessment of trends using years of data mostly before the most-recent reforms, including SB 863. A future study will present data from other sources and perspectives, including a survey administered to physicians participating in the WC system and an analysis of MPN listings.
Overall Findings and Limitations
The number of providers treating injured workers overall and in specific specialties is one measure describing injured workers' access to timely and appropriate care. All else equal, a greater number of providers treating injured workers likely represents better access to care.
Overall, fewer providers—measured in terms of separate billing practices1—provided care to California WC patients in 2014 than in 2010. We found 15 percent fewer providers in the 2014 WCIS data than in the 2010 data.
The specialties with the largest declines from 2010 to 2014 in WC-participating providers were family medicine/general practice (almost 5,600 fewer providers), chiropractic medicine (about 1,600 fewer providers), and pharmacy providers (about 700 fewer providers).2 Most other specialties were relatively stable (changes of fewer than 500), except physical therapists (increased by 554 providers) and other (increased by 670 providers).
Over the same period, there was an increase in the number of WC injuries. We might expect this to increase rather than decrease provider participation in treating WC patients.
Utilization and Payments per Provider
Measures of the number of claims (i.e., injuries) per provider, the number of bill lines (i.e., discrete medical services) per provider, and payments per provider are important complements to measures of provider participation. Per-provider utilization and payment measures help describe whether care for injured workers is concentrated among a few providers or distributed evenly across many providers. We caution that there are a wide range of factors that could affect these measures over time, including changing numbers or mix of workplace injuries, changes in clinical practice, and changes in WCIS data completeness. We also note that adjusting for multiple comparisons results in a loss of statistical significance for some of these trends.
- We found an increase in the average number of claims per provider from 2010 to 2014 (from 47 in 2010 to 59 in 2014; p = 0.018). Broken out by specialty, the number of claims per provider increased for most specialties, although this difference was only significant (at p < 0.01) for occupational medicine.3
- We found an increase in the average number of bill lines (or services provided) per provider, from 474 in 2010 to 540 in 2014, although this difference was not statistically significant.4
- Payments per provider increased by $8,813, on average, from 2010 to 2014 (p = 0.046). Payments increased for anesthesiology, behavioral health, and orthopedics providers by $6,893 (31 percent), $12,435 (22 percent), and $29,810 (27 percent), respectively.
- The observed increases in average claims per provider, bill lines per provider, and payments per provider were likely driven by changes in very large practices or health systems treating many injured workers. Changes in the median claims per provider were much lower for all three measures. For example, the median number of claims per provider was 2 in 2010 and 2014, and the median number of bill lines per provider was 12 in both years.
Utilization and Payments per Injury
Improving or declining access to care among injured workers could result in changes in the observed volume of, or payments for, services, particularly in the first year after injury.
- For most service categories, utilization within 12 months of injury declined from 2010 to 2014. It is not clear from this analysis whether the reduction in utilization over time was driven by a change in access to care, a change in physician incentives through the transition to a new resource-based relative value scale (RBRVS) fee schedule for practitioner services as part of SB 863 changes, or some other factor. Further research is needed to investigate whether these reductions raise access concerns.
- We found that payments for many service categories changed from 2010 to 2014. Payments per injury increased almost $96 for evaluation and management (E&M) services from 2010 to 2014 but declined for almost all other types of services (except surgery and prosthetics/orthotics) (all p < 0.01). Some of these changes—for example, increases in payments for E&M services—are consistent with higher payment rates implemented through the transition to RBRVS in 2014. Again, it is not clear from these analyses whether SB 863 provisions or other factors are driving these observed changes.
Timeliness of Care
We measured the timeliness of care by examining how quickly injured workers see a provider from the date of injury to the first visit. We focused on the time from injury to ambulatory E&M visits with providers. These visits are the appropriate first service for most workplace injuries.
- Overall, we found a small increase in the median wait time between injury and any E&M visit, from 2 days in 2010 to 3 days in 2014.
- The pattern is similar between Northern and Southern California, but there were differences in timeliness of care between types of injury.
- For comparison, the average wait time to see a provider in the Texas WC system was about four days (Texas Department of Insurance, 2016), the average wait time to see a physician among 15 large markets was 24 days, and the average wait time to see an orthopedic surgeon specifically was 11 days (Merritt Hawkins, 2017).
Monitoring Provider Churn
Injured workers may see a greater number of primary care providers (PCPs) in the year following initial treatment if they are having difficulties scheduling follow-up care with the initial PCP. Overall, we found that PCP churn—or switching from one PCP to another—decreased from 2010 to 2014. The average number of PCPs seen in the year following injury fell slightly, from 1.24 to 1.21, and was relatively similar across injury types.
Pathways of Care
We examined "pathways of care,"" defined by the initial visit setting and provider type and up to three visits thereafter. An analysis of this type could identify the symptoms of access issues—for example, if large shares of injured workers had unusual sequences of services or long gaps between services. Overall, we found that the majority of injured workers (between 61 and 65 percent) had their first visit with a PCP for an E&M visit; this has been relatively stable over time. Other key takeaways of our analyses on pathways of care include the following:
- Having the first visit in an emergency room occurred in only about 10 percent of injuries, with most of those injuries not resulting in an inpatient admission. Those injured workers, not surprisingly, had the shortest amount of time between the injury date and first visit.
- Injured workers who started with an E&M visit were typically seen within one day of injury, with the second visit typically occurring four to five days later when it was with a nonspecialist and about ten to 13 days later when it was to see a specialist; that number increased somewhat over time. Injured workers in these pathways typically had another seven days' wait between the second and third visits.
- The average number of bill lines in a 12-month period following injury varied considerably across these different pathways, as well as over time. In the majority of pathways that we studied, utilization increased over time.
The main limitation of our analysis stems from our use of the TIN as a provider identifier. The range of health care delivery entities that can bill under a single TIN—from solo physician practices to large integrated health systems—results in extraordinary heterogeneity in the number of claims, bill lines, and payments per TIN. Furthermore, we expect the number of TINs treating injured workers to decrease over time because of consolidation in the broader health care system, rather than because of decisions to stop treating injured workers. The most recent WCIS release requires an individual-level practitioner identifier (NPI), which will benefit future analyses.
There are more-general limitations to using the WCIS medical data. First, not all WC claims are reported into the system. Additionally, among reported claims, there is underreporting of initial medical visits and of medical bills. As a result, our results are from WCIS-reported injuries and medical bills only and cannot be interpreted as applying to the entire California WC system or to all of providers' care to injured workers.
We also note that the measures of access to care that we examined are not exhaustive, and there may be other relevant measures that act as a proxy for, or are related to, access to care for injured workers. In future reports, we will explore other measures, including provider-based measures and measures based on the network of providers. RAND is also separately conducting a study on the effect of the SB 863 reforms on medical care and work-related outcomes that may be of interest (Mulcahy et al., forthcoming).
For this study, we focused on a set of access measures that can be derived from administrative and medical bill data to monitor trends in WC medical care and identify potential issues that merit further analysis. Although we found that fewer providers are treating injured workers over time, the lack of a consistent individual-practitioner identifier throughout our study period is a serious limitation. We generally found increases in claims, bill lines, and spending per provider. Although these increases were moderate to large in number, many of the differences were not statistically significant. These results suggest a concentration of treatment for injured workers, in which a relatively smaller number of providers furnished care to injured workers. Increasing concentration could offer opportunities for specialization in the treatment of work-related injuries. On the other hand, increasing concentration could lead to future access barriers related to scheduling. We also found that the timeliness of care in the California WC system compared favorably to the timeliness of care in other states, although the median time from injury to first treatment did increase slightly over the study period. Finally, we found that most injured workers followed what appears to be an appropriate pathway of care through treatment, including an initial evaluation and management visit with a PCP.