Table 3
Summary of included studies 1991–2017
| References | Year | Design | Data source | Sample | Intervention and comparison | Costs measured | Time interval | Outcomes |
|---|---|---|---|---|---|---|---|---|
| Hong [33] | 2017 | CO | Insurance claims 2010–2014 | 878,720 adults with acute uncompli-cated back pain and 492,805 adults with acute uncompli-cated headache | 100,977 clinicians, including PCMD vs DC vs specialist MD | Imaging | 1 year | DCs did less imaging (17%) than specialists (36.5%) and more than PCMD (13.3%). DCs had higher Odds Ratio (OR) higher for imaging if they |
| Owned X-ray equipment | ||||||||
| Had imaged prior patient | ||||||||
| Hurwitz [34] | 2016 | CO | Blue Cross Blue Shield of NC claims by NC State Health Plan for Teachers and State Employees 2000–2009 | 2,795,046 UNP claims and 529,318 complicated neck pain CNP claims 2000–2009 | DC alone, MD + PT, MD + DC, referrals (hospitals, emergency medicine, specialists, etc.) | Total cost of care for ICD9 diagnosis for one fiscal year | 1 fiscal year | Costs excluding referral services: For UNP or CNP, MD + PT > MD + DC |
| Costs including referral services: UNP or CNP: MD + PT > MD + DC | ||||||||
| UNP total charges: 54%-84% lower for DC | ||||||||
| Hurwitz [35] | 2016 | CO | Blue Cross Blue Shield of NC claims by NC State Health Plan for Teachers and State Employees 2000–2009 | 2,075,866 ULBP claims and 1,083,496 CLBP claims 2000–2009 | DC alone, MD + DC, MD + DC, referrals (hospitals, EM,specialists, etc.) | Total cost of care for ICD9 diagnosis for one fiscal year | 1 fiscal year | Costs for ULBP: |
| DC alone or MD + DC < MD alone or MD + PT | ||||||||
| Costs for CLBP: | ||||||||
| DC alone or MD + DC > MD alone or MD + PT | ||||||||
| Risk-adjusted: | ||||||||
| MD + DC < MD + PT and | ||||||||
| MD alone > DC alone for ULBP and CLBP | ||||||||
| Weeks [41] | 2016 | CO | Medicare data 2006–2012 | 40,720 multiply comorbid patients aged 66 and older with cLBP episodes who were enrolled in Medicare Part D (56.3% of the total sample of 72,326) | 1) CMT alone; 2) CMT followed by MD; 3) MD followed by CMT; 4) MD alone | Cost of care including pain medications | per episode costs | Costs and episode length: |
| CMT alone < any other group | ||||||||
| CMT + MD < ,MD alone | ||||||||
| Weeks [40] | 2016 | CO | Medicare data | Medicare patients in 2011 within the 306 Dartmouth hospital referral regions | Areas with higher and lower DC use by Medicare patients | Opioid prescriptions and Medicare payments to DCs | 1 year | Higher DC costs (more usage) were associated with lower opioid prescriptions, but not with lower opioid doses in those with prescriptions |
| Leininger [52] | 2016 | CS using RCT data | RCT data | 241 adults aged ≥ 65 | Home exercise and advice (HEA) vs spinal manipulative therapy (SMT) plus HEA vs SRE plus HEA | Direct and indirect healthcare costs and clinical outcomes (pain, disability and QALY) | 1 year | On average, SMT + HEA had better clinical outcomes and lower total societal costs than SRE + HEA and HEA alone, with a 0.75 to 0.81 probability of cost-effectiveness for willingness to pay thresholds of $50,000 to $200,000 per QALY |
| Fritz [32] | 2015 | CO | Claims data from University of Utah Health Plans 2012–2013 | 747 patients with new LBP claim | First provider | Number of: | 1 year | DC first: |
| 1) Primary care MD 2) Physiatry | radiographs | Decreased risk for advanced imaging | ||||||
| 3) DC | Advanced imaging | Surgeon visit | ||||||
| 4) PT | Surgeon office visit | Increased episode of care duration | ||||||
| 5) Spine surgeon-Ortho/ neuro | Surgical procedure | |||||||
| 6) ER | Epidural injection | |||||||
| 7) Specialist | LBP-related EM | |||||||
| Costs: total allowed costs for all claims | ||||||||
| Keeney [26] | 2013 | PCO | Disability Risk Identification Study Cohort (D-RISC) | 1885 WA state injured workers | First provider: DC vs. MD (occmed) vs MD (surgeon) | Early predictors of lumbar spine surgery, by type of provider | 3 years | OR of surgery within 3 yrs: 1st provider-Surgeon 10.4; MD occmed 2.1; DC 0.2 |
| Surgery: | ||||||||
| 43% of workers with surgeon first | ||||||||
| 2% with DC first | ||||||||
| Graves [25] | 2012 | PCO | Disability Risk Identification Study Cohort (D-RISC) | 1830 WA state injured workers | First provider: DC vs MD (primary care) vs MD (occ med) vs MD (surgeon) vs ED vs other type (specialist or physical med) | Early predictors of early MRI, by type of provider | 3 years (2002–2004); early MRI = lumbar MRI ≤ 42 days post injury | IRR (incident rate ratio): |
| PCMD: 1.0 | ||||||||
| DC: 0.6 | ||||||||
| MD occ med: 1.4 | ||||||||
| Surgeon: 1.5 | ||||||||
| ED: 1.0 | ||||||||
| Other: 1.2 | ||||||||
| DC first: | ||||||||
| approximately 50% lower likelihood of early MRI as compared to PC MD | ||||||||
| Liliedah l[38] | 2010 | CO | Blue Cross/Blue Shield TN records 2004–2006 | 85,402 patients with LBP | First provider: DC vs MD/DO | Cost of LBP care per episode(Total episode costs included costs paid for all services provided during the episode by any providers, including pharmaceuticals | By episode during the 2-year study period | Cost of episodes with initial DC, adjusted for risk, were 20% less than with initial MD |
| Grieves [47] | 2009 | CS | WI private HMO insurance claims database of ~ 30,000 | Patients with at least 1 medical or chiropractic visit for LBP | Primary medical vs chiropractic vs specialist medical care | Mean total back pain claims for procedures by provider (DC or MD); medication costs not included | 2 years | Per case, mean chiropractic cost was $851 and for all forms of medical care, $2784 |
| 2004–2005 | (n = 896) | Per case, median primary care medicine charges were $365; and $576 for all medical management; chiropractic $417 and specialist medical care $669 | ||||||
| Haas [48] | 2005 | CS | Practice-based research network over 2-year period (1994–1996) | 2872 patients with acute or chronic LB | Chiropractic care to primary medical care | Chart audit for a period of 12 months after baseline; office cost estimates based on Medicare/ ChiroCode relative value units and Medicare conversion factors. Estimated total costs included in-office costs plus estimated costs of advanced imaging, surgical consultation and physical therapist referrals | 3 and 12 months from baseline visit | Adjusted DC office costs were 1.5–2.0 × greater than MD, but total costs of DC and MD treatment did not differ significantly at 3-months or 12-months when costs of advanced imaging and referrals are included |
| Greater improvement in pain and disability with DC care vs MD care, without additional costs | ||||||||
| Kominski [50] | 2005 | CS using RCT data | RCT data from records of a large medical practice treating HMO patients | 681 patients with LBP | MD only, MD + PT, DC only, DC + PM | Total outpatient costs, excluding pharmaceuticals | 18 mo | Adjusted mean outpatient costs: MD + PT $760 |
| DC + PM $579 | ||||||||
| DC $560 | ||||||||
| MD $369 | ||||||||
| Nelson [54] | 2005 | CS | Managed care insurance claims database from 1/1/97 through 3/30/01 | Entire population of patients with chiropractic benefit (707,690) and without chiropractic benefit (1,001,995) | Insurance claims by patients for back or neck pain enrolled in medical plans with a chiropractic benefit vs those without a chiropractic benefit | Rates of advanced imaging, surgery, inpatient care, and plain-film radiographs | 4-year | For patients with low back or neck pain use rates of all 4 studied procedures were significantly lower in the group with chiropractic coverage |
| Legorreta [51] | 2004 | CS | Administrative claims data from a large CA regional managed-care network | 707,690 health plan members with an additional chiropractic coverage benefit; 1 M | Costs associated with episodes of care for patients with NMSK conditions receiving only DC care vs those receiving only MD care | Total healthcare claim costs, individual components of total costs (such as inpatient and outpatient services); costs of NMSK care at the episode level | 4-year | Lower with DC care: |
| without the chiropractic benefit | 12% per member per year (PMPY) excluding medication costs | |||||||
| 13% PMPY costs with NMS patients | ||||||||
| Mean cost of DC back pain treatment was $522 (8% lower than patients without chiropractic) | ||||||||
| Complicated back pain episodes were only marginally higher (10% vs 8%) for MD vs DC care | ||||||||
| DC back pain patients had significantly fewer hospital days; lower MRI rate; lower surgery rate, fewer radiographs, and were less likely to have comorbidities | ||||||||
| Phelan [55] | 2004 | CS | 1975–1994, North Carolina Industrial | 43,650 claims | Total cost of medical vs chiropractic management of injured workers in NC | Lost work days, Temporary Total Disability (TTD), MD cost, DC cost, hospital inpatient cost, hospital outpatient cost, total medical cost, compensation paid, and total cost of claim | All closed claims 1975–1994 | LB injury: mean costs were $3425 for MD and $634 for DC. Compensation payments averaged $15,819 for patients with MDs, $1912 with DCs |
| Commission closed injury claims | Mean lost workdays for MD care were 175; for DC care, 25. Mean total claim cost (including compensation) managed by MD was | |||||||
| $23,562; for DC it was $2597. Note: There was only 0.8% DC utilization in this study, compared to 85.4% MD utilization | ||||||||
| Stano [61] | 2002 | CS | Practice-based research network (1994–1996) | 2872 patients with acute or chronic LB | Total cost of care for 922 medical patients vs cost of care for 1,950 chiropractic patients | Office visits and treatment utilizing CPT, RVU | 1 year from initial visit | Mean office cost of DC care $214; MD non-referral care $103 (including prescriptions); with same degree of relief. Referral treatment, surgery, post-surgical care and advanced imaging costs excluded |
| Cherkin [63] | 1998 | RCT | RCT data from Group Health Cooperative of Puget Sound HMO | 321 adults with LBP that persisted for 7 days after primary care visit | PT McKenzie method vs CMT vs provision of an educational booklet | Total costs to the HMO (no out-of-pocket expenses) including medications | Treated for 1 month; followed up for 2 years | 2-year mean costs: |
| PT $437 | ||||||||
| $429 CMT | ||||||||
| $153 for the booklet group | ||||||||
| No significant differences in clinical outcomes | ||||||||
| Smith [57] | 1997 | CS | MEDSTAT data from approximately 2 million beneficiaries | 1215 patients (medical or chiropractic first) | Total cost and outcomes of medical vs chiropractic care for NMSK diagnoses | Total costs via total insurance and outpatient payments and patient retention | 2 years | Total insurance payments greater for medically initiated episodes. Patients who "cross over" between providers are more likely to return to chiropractic providers |
| Mosley [53] | 1996 | CS | HMO data 1994–1995 | 121 chiropractic patients and 1838 medical care patients | Chiropractic vs medical patients with neck or back pain | Total cost of care including diagnosis, imaging, prescription meds, | 1 year | Overall costs per patient: chiropractic = $539 vs medical = $774 |
| Imaging rate: chiropractic 5% vs 17% and cost/patient $31 vs $94 | ||||||||
| # of prescriptions/pt: chiropractic 1 vs 2, Rx avg cost: Chiropractic-$3.25, Medical = $7.20 | ||||||||
| Stano [62] | 1996 | CS | MEDSTAT data from approximately 2 million beneficiaries | 6183 patients (medical or chiropractic first) | Chiropractic vs medical patients with NMSK diagnoses | Total costs and episodes | 2 years | Mean total payments for first episodes: Chiropractic $518 vs $1020 |
| Episode length: Chiropractic: 37 days vs 19 days | ||||||||
| Shekelle [56] | 1995 | CS | RAND Health Insurance Experiment | 686 patients | Chiropractic vs various types of medical care for patients with back pain (general practitioners, orthopedists, internist, DO, and all others.) | Number of visits per episode and mean costs per visit; total costs of episodes by provider type | 4 wks before 1st visit to 4 wks after last visit | Mean provider cost/episode: |
| DC $264; Ortho $247; DO $238; PC MD $95. Mean costs per visit: | ||||||||
| DC $19.45; PC MD $20.21; orthopedist $38.53, DO $22.18 | ||||||||
| Carey [23] | 1995 | PCO | Practice-based research network in NC | 1633 patients with acute LBP | DC vs MD PC vs orthopedic surgeon | Total cost per episode of LBP (ambulatory) | 24 weeks | Median costs/episode (urban): |
| DC $545 | ||||||||
| PCMD $169 | ||||||||
| Surgeon $383 | ||||||||
| Stano [60] | 1994 | CS | MEDSTAT claims data from 395,641 patients with neuromusculoskeletal conditions.1988–1990 | Patients receiving only medical/DO care; only chiropractic care; or both | Chiropractic plus medical/DO care vs medical/DO care only for patients with NMSK diagnoses | Total costs and hospital admission rates | 2 years | Overall lower costs for patients using both chiropractic and medical care are attributable to lower rate of hospital admissions. Total cost outcomes: DC only = $4379, MD only = $5360 |
| Other spinal diagnoses also showed similar lower DC cost | ||||||||
| Stano [59] | 1993 | CS | MEDSTAT data from approximately 2 million beneficiaries; 1988–1990 | 8928 patients with low back conditions with insurance that did not restrict chiropractic | Chiropractic vs medical/DO patients with LBP diagnoses | Total costs and episodes | 2 years | Mean total payments: |
| Chiropractic $573 vs $1112 | ||||||||
| Episode length: | ||||||||
| Chiropractic: 39 days vs 22 days | ||||||||
| Stano [58] | 1993 | CS | MEDSTAT claims data from 395,641 patients with neuromusculoskeletal conditions | Patients receiving only medical care; only chiropractic care; or both | Chiropractic plus medical care vs medical care only for patients with NMSK diagnoses | Total costs and hospital admission rates | 2 years | Lower costs for patients using both chiropractic and medical care are attributable to lower rate of hospital admissions |
| Jarvis [49] | 1991 | CS | Workers Compensation claims for UT 1986 | 3062 workers with back injury claims treated by either MD or DC | Chiropractic vs medical costs for workers with back injuries | Total cost per case of care and compensation | 2 years | Mean cost of care: DC $527 vs MD $684 |
| Mean days of compensation: DC 2 vs MD 21 | ||||||||
| Mean compensation: | ||||||||
| DC $68 vs MD $668 |
Study design: CO, retrospective or cross-sectional cohort study; CS, cost study; PCO, prospective cohort study; RCT, randomized controlled trial
AC Acupuncturist; cLBP Chronic low back pain; CLBP Complicated low back pain; CMT Chiropractic manipulative treatment; CNP Complicated neck pain; DC Chiropractor or chiropractic care; DO Osteopathic physician or osteopathic care; ED Emergency department; EM Emergency medicine; HEA Home exercise advice; HMO Health maintenance organization; LBP Low back pain; MD Medical physician or medical care; MRI Magnetic resonance imaging; Neuro Neurosurgeon; NMSK Neuromusculoskeletal; Occmed Occupational medicine; OMT Osteopathic manipulative therapy; OR Odds ratio; Ortho Orthopedist/orthopedic surgeon; PCMD primary care medical physician; PM Physical modalities; PMPY Per member per year; PT Physical therapist or physical therapy care; QALY Quality-adjusted Life Year; SMT Spinal manipulative therapy; SRE Supervised rehabilitative exercise; ULBP Uncomplicated low back pain; UNP Uncomplicated neck pain