Craig F Nelson, DC, MS, Doug Metz, DC,
Antonio Legorreta, MD, MPH, Thomas LaBrot, DC
Health Services Research Consulting
Introduction: Health insurance coverage for chiropractic care is
restricted compared to most other health care services. A barrier to
insurance plan coverage of chiropractic care is the lack of data regarding
the effects of such coverage on overall health care utilization and costs.
The study evaluates the effects of chiropractic coverage on selection
(age, gender, comorbidities), total health care costs, rate of utilization
of specific high-cost procedures, cost of management of specific NMS
conditions, and whether chiropractic care is used as substitution care or
Methods: A four-year longitudinal study using administrative claims data compared 700,000 health plan members with chiropractic coverage to 1
million health plan members without chiropractic coverage. There are six
distinct cohorts of patients that are evaluated and compared in this study:
Cohort A: Patients in health plans that do cover chiropractic care.
Cohort B: Patients in health plans that do not cover chiropractic care.
Cohort A1: Patients in health plans that cover chiropractic care who had
any treatment for NMS conditions.
Cohort B1: Patients in health plans that do not cover chiropractic care
who received medical treatment for their NMS conditions.
Cohort A1a: Patients in health plans that do cover chiropractic care who
received chiropractic treatment for their NMS conditions.
Cohort A1b: Patients in health plans that do cover chiropractic care who
received medical treatment for their NMS conditions.
Results: Members with chiropractic coverage were younger (mean age = 33 vs. 36 years, p<0.0001) and less likely to have specific comorbid medical
conditions (-<0.0d for six selected medical conditions) as compared to
those without chiropractic coverage. Total health care costs for members
with chiropractic coverage was 12% lower than plan members without
coverage. Among all health plan members who were treated for NMS
conditions, total health care costs were 13% lower among those with
coverage compared to those without. The cost of treating episodes of low
back pain was 28% lower in the group with chiropractic coverage, and the
aggregate cost of back pain care per patient over the four-year period was
8% lower in the covered group. Back pain patients with chiropractic
coverage had fewer inpatient stays than did those without chiropractic
coverage (9.3 vs. 15.6 stays per 1,000 patients, p<0.001). The MRI rate
was also lower for back pain patients with chiropractic coverage as
compared to those without chiropractic coverage (43.2 vs. 68.9 MRIs per
1,000 patients, p<0.001). The rate of lower back surgery among patients
with chiropractic coverage was lower as well (3.3 vs. 4.8 surgeries per
1,000 patients, p<0.001). Back pain patients with chiropractic coverage
also received fewer radiographs (17.5 vs. 22.7 per 1,000 patients,
p<0.001) than did back pain patients without chiropractic coverage. The
data also demonstrate that most chiropractic care is substitution for
medical care within the health plan.
Conclusion: This study demonstrates that the inclusion of a chiropractic benefit in a managed health care plan results in a reduction in the
overall utilization of health care resources, and thereby, cost savings.
There are four mechanism that produce this cost reduction: 1. A favorable
selection process; 2. A substitution effect of chiropractic care for
medical care; 3. Lower rates of use of high cost procedures; 4. Lower cost
management of care episodes by chiropractors.
CREDITS: This article was provided by FCER, and has been submitted for publication to Archives of Internal Medicine. It will be presented as a poster presentation at the World Federation of Chiropractic's Congress, to be held in Orlando, Florida, on May 1-3, 2003.