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Original Contribution| Volume 39, ISSUE 5, P381-386, June 2016

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Trends in the Use and Characteristics of Chiropractic Services in the Department of Veterans Affairs

  • Anthony J. Lisi
    Correspondence
    Submit requests for reprints to: Anthony J. Lisi, DC, 950 Campbell Ave, Mail Stop 111D, West Haven, CT, 06516.
    Affiliations
    Chiropractic Section Chief, VA Connecticut Healthcare System, West Haven, CT

    Assistant Clinical Professor, Yale Center for Medical Informatics, Yale University School of Medicine, New Haven, CT
    Search for articles by this author
  • Cynthia A. Brandt
    Affiliations
    Staff Physician, VA Connecticut Healthcare System, West Haven, CT

    Professor, Yale Center for Medical Informatics, Yale University School of Medicine, New Haven, CT
    Search for articles by this author

      Abstract

      Objectives

      The purpose of this study was to analyze national trends and key features of the Department of Veterans Affairs’ (VA’s) chiropractic service delivery and chiropractic provider workforce since their initial inception.

      Methods

      This was a serial cross-sectional analysis of the VA administrative data sampled from the first record of chiropractic services in VA through September 30, 2015. Data were obtained from VA’s Corporate Data Warehouse and analyzed with descriptive statistics.

      Results

      From October 1, 2004, through September 30, 2015, the annual number of patients seen in VA chiropractic clinics increased from 4052 to 37349 (821.7%), and the annual number of chiropractic visits increased from 20072 to 159366 (693.9%). The typical VA chiropractic patient is male, is between the ages of 45 and 64, is seen for low back and/or neck conditions, and receives chiropractic spinal manipulation and evaluation and management services. The total number of VA chiropractic clinics grew from 27 to 65 (9.4% annually), and the number of chiropractor employees grew from 13 to 86 (21.3% annually). The typical VA chiropractor employee is a 45.9-year-old man, has worked in VA for 4.5 years, and receives annual compensation of $97860. VA also purchased care from private sector chiropractors starting in 2000, growing to 159533 chiropractic visits for 19435 patients at a cost of $11155654 annually.

      Conclusions

      Use of chiropractic services and the chiropractic workforce in VA have grown substantially over more than a decade since their introduction.

      Key Indexing Terms

      The Department of Veterans Affairs (VA) operates the largest integrated health care system in the United States, including144 hospitals, more than 1400 other health care facilities, and a workforce of more than 326000.
      • Department of Veterans Affairs
      Selected veterans health administration characteristics: FY2002 to FY2013.
      More than 9 million of the approximately 22 million living US Veterans are enrolled in VA’s health care system.
      • Department of Veterans Affairs
      Number of veteran patients by healthcare priority group: FY2000 to FY2014.
      Each year, approximately 7 million of those enrolled receive health care services at VA facilities, including more than 86 million outpatient visits and 700000 admissions.
      • Department of Veterans Affairs
      National center for veterans analysis and statistics pocket cards.
      The VA recently began a 2-phased approach to introduce chiropractic care to its complement of health care services. In 1999, Public Law 106-117
      Public Law 106-117—Veterans Millennium Health Care and Benefits Act.
      authorized VA to provide chiropractic care by purchasing these services from private sector chiropractors. VA Directive 2000-014, issued May 5, 2000, established VA’s first policy on chiropractic care and enabled VA facilities to begin purchasing chiropractic care. Subsequently, in 2001, Public Law 107-135
      Public Law 107-135. Department of Veterans Affairs Health Care Programs Enhancement Act of 2001.
      added chiropractic care to the standard medical benefits available to all eligible VA patients and authorized VA to deliver these services on-site at a minimum of 21 medical facilities. VA Directive 2004–035, issued July 16, 2004, updated VA chiropractic policy and enabled VA facilities to begin delivering on-station chiropractic care by hiring and/or contracting with licensed doctors of chiropractic (DCs).
      Since then, VA has expanded its delivery of chiropractic care
      Fact sheet for chiropractic services. Rehabilitation and Prosthetic Services, Veterans Health Administration, Department of Veterans Affairs.
      ; but currently, little detail is known about the use of VA chiropractic services over time, details of these services, or characteristics of the VA chiropractic workforce. The purpose of this study was to analyze national trends and key features of VA’s chiropractic service delivery and chiropractic provider workforce since their initial inception.

      Methods

      This study was a serial cross-sectional analysis of VA administrative data. The data used in this work were obtained from VA’s Corporate Data Warehouse and were analyzed using ProClarity (ProClarity Corp, Boise, ID) and Microsoft Excel (Microsoft Corp, Redmond, WA). The project was approved by the Institutional Review Board of the VA Connecticut Healthcare System.
      VA administrative data are tracked by fiscal year (FY), running from October 1 of a given calendar year through September 30 of the next. Information on chiropractic services provided on-site at VA facilities (including visits, patient factors, and services delivered) was identified in VA corporate data by the numeric code (Stop Code) 436. We obtained Stop Code 436 data from both the primary and secondary code positions, which allow for capturing chiropractic workload data whether it was assigned to a chiropractic clinic or to a different clinic in which a DC may be providing care (eg, pain medicine, primary care).
      Information on the chiropractic workforce (on-site employees) was identified by the occupational code 0604 for FY 2005 through FY 2013. Beginning in FY 2014, VA changed this code as part of a national data management reorganization; thus, for subsequent fiscal years, we used occupational code 0601, subcode 97.
      Data on chiropractic care purchased from private chiropractors (also known as fee-basis care) were obtained using the numeric code (Purpose of Visit Code) 75.
      Data were sampled from the first record of VA chiropractic services and workforce through the end of FY 2015. We assessed all available data and did not attempt to account for missing elements. Data were analyzed using descriptive statistics.

      Results

      On-Station Chiropractic Services

      Eleven patient visits to 3 VA on-station chiropractic clinics were identified in FY 2004 data, reflecting the first few clinics that were established before October 1, 2004. However, for on-station chiropractic services and workforce trend analyses, the 11-year time frame of FY 2005 through FY 2015 (October 1, 2004, through September 30, 2015) is presented in this article.
      On-station chiropractic use is shown in Figure 1. From FY 2005 to FY 2015, the total number of patients seen each year in VA chiropractic clinics increased from 4052 to 37349 (approximately 112% in the first year, then an average of 18% per year thereafter, with a total increase of 821.7% over the 11-year period). During this same time, the number of annual chiropractic visits increased from 20072 to 159366 (approximately 130% in the first year, then an average of 15% per year thereafter, with a total increase of 693.9% over the 11-year period).
      Figure thumbnail gr1
      Fig 1Total number of unique patients receiving on-station VA chiropractic care and total number of on-station chiropractic encounters.
      We analyzed select patient demographics; International Classification of Diseases, Ninth Revision (ICD-9) codes; and Current Procedural Terminology (CPT) codes for on-station chiropractic visits in each fiscal year and report FY 2014 as a representative example. In that year, 15.8% of patients seen in VA chiropractic clinics were female compared with 9.7% of the general VA outpatient population. As shown in Figure 2, patients in VA chiropractic clinics were somewhat younger than the general VA outpatient population. These demographics varied very little each year from FY 2005 through FY 2015.
      Figure thumbnail gr2
      Fig 2Age distribution of patients receiving on-station chiropractic care compared with all VA patients receiving any on-station outpatient services for FY 2014.
      The primary ICD-9 diagnostic codes assigned to each on-station chiropractic visit each fiscal year were captured and collapsed into broad categories for year-to-year comparison. In FY 2014, approximately 59.2% of chiropractic visits were assigned primary diagnostic codes for low back conditions; 24.3%, neck conditions; 10.4%, other or nonspecific musculoskeletal conditions; and 6.1%, thoracic conditions. This distribution varied very little each year from FY 2005 through FY 2015.
      The CPT codes assigned to each chiropractic visit each year were captured and also collapsed into broad categories for year-to-year comparison. In FY 2014, approximately 49.5% of visits were assigned chiropractic spinal manipulation codes; 21.2%, evaluation and management; 12.6%, physical modalities; 9.3%, other manual therapies; 4%, acupuncture; and 3.4%, exercise/active care. From FY 2005 through FY 2015, there were a 10.2% increase in the use of exercise/active care codes and a 6.9% decrease in the use of physical modality codes, whereas use of the remaining CPT codes was relatively stable.

      Chiropractic Workforce

      During the study period, the total number of VA chiropractic clinics grew on average 9.4% per year (from 27 to 65), and the number of chiropractor clinician employees grew on average 21.3% each year (from 13 to 86 employees). Key characteristics of the chiropractic employee workforce are presented in Table 1. The typical VA chiropractor employee is a 45.9-year-old man, has worked in VA for 4.5 years, and receives annual compensation of $97860.
      Table 1VA Chiropractor Employee Workforce Trends
      Fiscal YearTotal OnboardTotal FemaleTotal FTEAverage AgeAverage Years ServedAverage Annual Salary
      2004
      2005138.841.40.8$72566
      200617114.044.51.8$77899
      200720117.344.42.6$82116
      200824122.145.43.5$86458
      200929226.244.63.7$89680
      201036430.145.54.3$88836
      201144637.445.14.2$91017
      201241637.046.05.0$93232
      201345842.545.85.6$96858
      2014631157.545.25.1$95748
      2015861678.245.94.5$97860
      FTE, full-time equivalent

      Purchased Chiropractic Care

      Seven patients receiving purchased chiropractic care were identified in FY 2000 data. This grew only slowly in the 5 fiscal years before the establishment of on-station chiropractic clinics. Then, as seen in Figure 3, from FY 2005 to FY 2015, the rate of growth increased more rapidly. In FY 2005, VA purchased 8244 private chiropractic visits for 1072 Veterans at a cost of $428667. In FY 2015, VA purchased 159533 private chiropractic visits for 19435 Veterans at a cost of $11155654.
      Figure thumbnail gr3
      Fig 3Total number of unique VA patients receiving purchased chiropractic care outside of VA, total number of those visits, and total dollar amount disbursed for purchased chiropractic services.

      Discussion

      Prior work on VA chiropractic services has included a provider survey,
      • Lisi AJ
      • Goertz C
      • Lawrence DJ
      • Satyanarayana P
      Characteristics of Veterans Health Administration chiropractors and chiropractic clinics.
      observational reports of patient outcomes,
      • Dunn AS
      • Green BN
      • Formolo LR
      • Chicoine DR
      Chiropractic management for veterans with neck pain: a retrospective study of clinical outcomes.
      • Dunn AS
      • Green BN
      • Formolo LR
      • Chicoine D
      Retrospective case series of clinical outcomes associated with chiropractic management for veterans with low back pain.
      • Dunn AS
      • Passmore SR
      • Burke J
      • Chicoine D
      A cross-sectional analysis of clinical outcomes following chiropractic care in veterans with and without post-traumatic stress disorder.
      • Lisi AJ
      Management of Operation Iraqi Freedom and Operation Enduring Freedom veterans in a Veterans Health Administration chiropractic clinic: a case series.
      a mixed-methods program assessment,
      • Lisi AJ
      • Khorsan R
      • Smith MM
      • Mittman BS
      Variations in the implementation and characteristics of chiropractic services in VA.
      and 2 randomized clinical trials.
      • Dougherty PE
      • Karuza J
      • Dunn AS
      • Savino D
      • Katz P
      Spinal manipulative therapy for chronic lower back pain in older veterans: a prospective, randomized, placebo-controlled trial.
      • Dougherty PE
      • Karuza J
      • Savino D
      • Katz P
      Evaluation of a modified clinical prediction rule for use with spinal manipulative therapy in patients with chronic low back pain: a randomized clinical trial.
      This current study reports details of national trends in VA chiropractic clinical services. Our results show that the use of chiropractic care and the chiropractic workforce in VA have grown dramatically since their inception in FY 2005. The 2001 law
      Public Law 107-135. Department of Veterans Affairs Health Care Programs Enhancement Act of 2001.
      mentioned above remains the only congressional mandate for VA to provide on-site chiropractic services. VA met the minimum requirement of this law in FY 2005; therefore, any expansion or development seen from FY 2005 through FY2015 represents the organic growth of this new service.
      This growth may be explained by multiple factors including the natural trend of diffusion of change in any large medical system,
      • Dacin MT
      • Goodstein J
      • Scott WR
      Institutional theory and institutional change: introduction to the special research forum.
      • Scott T
      • Mannion R
      • Davies HT
      • Marshall MN
      Implementing culture change in health care: theory and practice.
      unique aspects (such as patient demand, patient access) related to the VA system,
      • Denneson LM
      • Corson K
      • Dobscha SK
      Complementary and alternative medicine use among veterans with chronic noncancer pain.
      • Burton TM
      VA halted visits to troubled hospitals.
      and/or the successful performance of VA chiropractors.
      • Lisi AJ
      • Khorsan R
      • Smith MM
      • Mittman BS
      Variations in the implementation and characteristics of chiropractic services in VA.
      This last aspect may be particularly relevant because, historically, chiropractic services were very rarely included in US hospital systems, which presented significant operational and cultural barriers for VA to implement these services.
      • Lisi AJ
      • Khorsan R
      • Smith MM
      • Mittman BS
      Variations in the implementation and characteristics of chiropractic services in VA.
      Because little is known about the introduction of chiropractic services to other US integrated hospital systems, there are no obvious comparators against which to gauge the manner, rate, and extent of penetration of these services in VA. Consequently, the reported trends in chiropractic use in VA depict the actual development of the program but may or may not reflect optimal practice patterns. This work did not attempt to assess patient-oriented outcomes, substitution of other services, or any other measure of impact associated with VA chiropractic care. Yet, the fact that these services have expanded consistently and substantially beyond the minimum mandated level may suggest that some VA decision-makers perceive value in providing chiropractic care.
      Our results indicate that VA chiropractic clinics saw a greater percentage of female and younger patients compared with the national VA outpatient population. This demographic tendency is consistent with the cohort of Veterans from the recent conflicts in Iraq and Afghanistan, which is known to have a high prevalence of musculoskeletal conditions.
      • Analysis of VA Health Care Utilization among Operation Enduring Freedom (OEF)
      • Operation Iraqi Freedom (OIF)
      • Operation New Dawn (OND) Veterans
      Office of Public Health, Veterans Health Administration, Department of Veterans Affairs.
      We identified ICD-9 and CPT codes assigned to on-station VA chiropractic visits, suggesting that VA chiropractors are seeing patients for similar conditions and providing similar services as previously reported in private sector
      • Mootz RD
      • Cherkin DC
      • Odegard CE
      • Eisenberg DM
      • Barassi JP
      • Deyo RA
      Characteristics of chiropractic practitioners, patients, and encounters in Massachusetts and Arizona.
      and other VA
      • Lisi AJ
      • Goertz C
      • Lawrence DJ
      • Satyanarayana P
      Characteristics of Veterans Health Administration chiropractors and chiropractic clinics.
      work. Our study did not aim to assess patient complexity; however, other work has shown that VA patients with musculoskeletal pain conditions carry a high burden of disease.
      • Kelsall HL
      • McKenzie DP
      • Forbes AB
      • Roberts MH
      • Urquhart DM
      • Sim MR
      Pain-related musculoskeletal disorders, psychological comorbidity, and the relationship with physical and mental well-being in Gulf War veterans.
      • Goulet JL
      • Kerns RD
      • Bair M
      • et al.
      The musculoskeletal diagnosis cohort: examining pain and pain care among veterans.
      We noted only 1 change in the types of on-station chiropractic services over time: a trend of decreased frequency of physical modality codes and an increased frequency of exercise/active care codes. This could be explained by changes in coding and/or practice patterns among existing VA DCs or the addition of new DCs with new coding and/or practice patterns over time. It was beyond the scope of this work to attempt to explain the reasons for this change, but it is interesting to note that the change is consistent with current evidence on the management of low back pain,
      • Chou R
      • Qaseem A
      • Snow V
      • et al.
      Diagnosis and treatment of low back pain: a joint clinical practice guideline from the American College of Physicians and the American Pain Society.
      the condition most commonly seen by VA DCs.
      This study also reports chiropractor clinician workforce data obtained directly from human resources records rather than provider self-report. This may be one of the most accurate depictions of these data in the United States, albeit from a small, constrained provider population. VA managerial data show that very few DCs have left VA after being hired, and recent applicants for VA chiropractor positions typically outnumber available slots by more than a hundredfold; thus, VA positions appear to be in high demand by US DCs.
      Consistent with VA policy for all health care services, delivery of chiropractic services occurs through a combination of care provided on-station at VA facilities as well as care purchased from community chiropractors. Purchased care may be used to supplement on-station chiropractic care at a given facility (for instance, to meet demand that exceeds current on-station capacity), or it may be the only mechanism whereby that care is delivered (for instance, at a facility that does not have an on-station DC).
      The Department of Veterans Affairs’ use of purchased chiropractic care began slowly at first and then grew more parallel with its use of on-station chiropractic care starting in FY 2005. However, we identified differences in the broad utilization rates between the two. From FY 2005 through FY 2015, the average annual number of visits per patient was 9.3 for purchased chiropractic care vs 4.6 for on-station care. We did not attempt to assess the appropriateness of either of these rates, and multiple factors may be at play in explaining this difference. For instance, in an undersupplied chiropractic clinic, some patients may receive only 1 on-station VA chiropractic visit and then be sent for purchased care off-site. However, our finding is consistent with other work showing a similar disparity in on-site vs off-site chiropractic utilization provided by a self-insured employer.
      • Kindermann SL
      • Hou Q
      • Miller RM
      Impact of chiropractic services at an on-site health center.
      As VA continues to unroll chiropractic services to meet Veteran demand, we expect to see additional increases in the use of on-station chiropractic care, the number of chiropractor employees, and the amount of chiropractic care purchased in the community. Our results show a period of significant expansion, yet we do not know the optimal sustainable size for the VA chiropractic program. The challenge for VA is to grow its chiropractic program in a way that yields the best clinical outcomes, meets Veterans’ expectations, and helps control health care costs.

      Limitations

      All administrative databases are subject to data transmission, storage, and retrieval error. We did not attempt to identify or account for missing data, but previous work has shown that VA administrative data for on-station care are highly accurate in multiple patient parameters,
      • Noël PH
      • Copeland LA
      • Perrin RA
      • et al.
      VHA Corporate Data Warehouse height and weight data: opportunities and challenges for health services research.
      • Miller DR
      • Pogach L
      Longitudinal approaches to evaluate health care quality and outcomes: the Veterans Health Administration diabetes epidemiology cohorts.
      and we have prior experience in VA data retrieval
      • Lisi AJ
      • Burgo-Black AL
      • Kawecki T
      • Brandt CA
      • Goulet JL
      Use of Department of Veterans Affairs administrative data to identify veterans with acute low back pain: a pilot study.
      • Leslie DL
      • Goulet J
      • Skanderson M
      • Mattocks K
      • Haskell S
      • Brandt C
      VA health care utilization and costs among male and female veterans in the year after service in Afghanistan and Iraq.
      • Justice AC
      • Erdos J
      • Brandt C
      • Conigliaro J
      • Tierney W
      • Bryant K
      The Veterans Affairs Healthcare System: a unique laboratory for observational and interventional research.
      • Goulet JL
      • Brandt C
      • Crystal S
      • et al.
      Agreement between electronic medical record-based and self-administered pain numeric rating scale: clinical and research implications.
      ; thus, it seems unlikely that missing data would substantially change our results with respect to on-station chiropractic services or workforce. However, VA purchased care (fee-basis) data capture may be subject to regional variation in use of the identifying Purpose of Visit Code; thus, our results in this category may be underreported. ICD and CPT codes are commonly used to analyze trends in service use; however, because of variation in coding fidelity at the provider level, the interpretation of these codes is limited. This study reported workforce data on chiropractor employees only and did not include contractors. Also, we did not measure the chiropractic workforce’s percent effort distribution between clinical, administrative, research, and/or other position responsibilities. VA chiropractor workforce data cannot be extrapolated to chiropractors in other health care systems and/or private practice.
      Future work is needed to better understand the most advantageous structures and processes of VA chiropractic care, that is, those resulting in the best outcomes for Veterans. This should include assessing models of patient access as well as identifying characteristics of optimal chiropractic care (eg, patient selection, chiropractic management options, and treatment frequency and duration). Studies assessing the effect that the use of VA chiropractic services has on the use of other VA health care services will be valuable, along with studies assessing patent-oriented outcomes such as physical function and satisfaction. Lastly, it may be useful to explore the impact that the VA chiropractic experience—facilitators, barriers, and consequences of expansion—can have on the integration of chiropractic services in the broader US health care system.

      Conclusion

      Since their introduction more a decade ago, use of on-station chiropractic services in VA, the VA chiropractic workforce, and VA’s use of purchased chiropractic care have grown substantially. The types of conditions for which patients see VA chiropractors and the types of services they receive are similar to previous reports of chiropractic care in the United States. Because VA continues to expand its delivery of chiropractic care, ongoing work is needed to assess the delivery of these services so that they can be optimized to provide the most value to Veterans and the VA health care system.

      Funding Sources and Conflicts of Interest

      This work was supported in part by a grant from the NCMIC Foundation. No conflicts of interest were reported for this study.

      Contributorship Information

      • Concept development (provided idea for the research): A.L.
      • Design (planned the methods to generate the results): A.L., C.B.
      • Supervision (provided oversight, responsible for organization and implementation, writing of the manuscript): A.L., C.B.
      • Data collection/processing (responsible for experiments, patient management, organization, or reporting data): A.L., C.B.
      • Analysis/interpretation (responsible for statistical analysis, evaluation, and presentation of the results): A.L., C.B.
      • Literature search (performed the literature search): A.L.
      • Writing (responsible for writing a substantive part of the manuscript): A.L., C.B.
      • Critical review (revised manuscript for intellectual content; this does not relate to spelling and grammar checking): A.L., C.B.

      Practical Applications

      • From October 1, 2004, to September 30, 2016, the number of patients receiving chiropractic cervices on-site at VA facilities annually increased from 4052 to 37349.
      • During this same time, the number of patients receiving VA purchased chiropractic care increased from 1072 to 19435.
      • The typical on-site VA chiropractic patient is a man between the ages of 45 and 64 years seen for low back or neck conditions, and receives spinal manipulation as well as evaluation and management services.
      • The typical VA chiropractor employee is a 45.9-year-old man, has worked in VA for 4.5 years, and receives annual compensation of $97860.

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