Skip to main content

Table 1 Study design for cost comparisons in private health plans

From: A systematic review comparing the costs of chiropractic care to other interventions for spine pain in the United States

First author

Year

Location/Plan type

Data type/Source

Data start -Data end

Eligibility

Indication/Duration

# ICD-9 codes

Inclusion

Exclusion

# Insured/# Eligible/# Included

Allen [33]

2014

National/Self-insured employer

Claims/Navistar integrated databasee

1/1/2001 - 12/31/2009

Back pain diagnosis

Low back pain/Any

77

1. Back pain episodes identified by one or more of 77 ICD-9 codes 2. 6 months of recorded continuous coverage

Cancer diagnosis, retired, died during study period

NR/21,080/14,787d

Grieves [29]

2009

Wisconsin/HMO

Claims/Arise Health Plan

1/1/2004 - 12/31/2005

1. Continuously enrolled, and 2. Claim for visit to MD or DC for 12 ICD-9 codes

Low back pain/Any

12

1. Continuously enrolled; 2. Any claim for visit to MD or DC

Saw both MD and DC

30,000/NR/897

Liliedahl [32]

2010

Tennessee/NR

Claims/BlueCross BlueShield

10/1/2004 - 9/30/2006

1. Claim for 82 ICD-9 codes related to spine pain, and 2. CPT code for visit to MD, DO, ED, or DC

Spine pain/Any

82

CPT code for visit to MD, DO, ED, or DC

Episodes not related to MD, DO, ED, or DC, or with incomplete claims records

669,320/85,402/102,438d

Mosley [30]

1996

Louisiana/HMO

Claims/Community Health Network of Louisiana

10/1/1994 - 10/1/1995

Claim for ICD-9 codes 720.0 to 724.9 (potentially 68 different ICD-9 codes) related to back or neck pain

Back or neck pain/Any

68

Claims related to ICD-9 codes

NR

NR/1,959/1,959

Shekelle [31]

1995

National/Fee for service

Claims/RAND Health Insurance Experiment

NR (mean 3.6 months)b

Claim related to pain, swelling, or injury of back region

Pain, swelling, or injury of back/Any

NA

Any back-related claim as 1/2/3 symptom

1.Elderly; 2.Care paid by workers’ compensation

7,706/686/1,020d

Smith [27]

1997

National/Fee for service

Claims/MEDSTAT

7/1/1988 - 6/30/1990

10 % sample of claims for 493 ICD-9 codes related to MSK conditions or claims for chiropractic care

Low back conditions/Any

9

10 % sample with claim related to ICD-9 codes

Unknown first-contact provider type

2,000,000a/434,763/890

Stano [28]

1996

National/Fee for service

Claims/MEDSTAT

7/1/1988 - 6/30/1990

10 % sample of claims for 493 ICD-9 codes related to MSK conditions or claims for chiropractic care

Low back conditions/Any

9

10 % sample with claim related to ICD-9 codes

1. Unknown first-contact provider type; 2. Negative value claims

2,000,000a/434,763/6,183

Stano [23]

1995

National/Fee for service

Claims/MEDSTAT

7/1/1988 - 6/30/1990

10 % sample of claims for 493 ICD-9 codes related to MSK conditions

Low back conditions/Any

9

10 % sample with claim related to ICD-9 codes

Negativepayments

NR/434,763/6,799

Stano [24]

1994

National/Fee for service

Claims/MEDSTAT

7/1/1988 - 6/30/1990

Claim for 493 ICD-9 codes related to MSK conditions

Low back conditions/Any

15

Claim related to ICD-9 codes

1. Coinsurance >15 %; 2. Deductibles > $200; 3. No restrictions on chiropractic or medical care

NR/395,641/42,331

Stano [22]

1993

National/Fee for service

Claims/MEDSTAT

7/1/1988 - 6/30/1990

Claim for 493 ICD-9 codes related to MSK conditions

Low back conditions/Any

15

Claim related to ICD-9 codes

1. Did not meet deductibles; 2. Did not file claims; 3. Out-of-plan use; 4. Age >65

2,000,000a/395,641/99,675

Stano [25]

1993

National/Fee for service

Claims/MEDSTAT

7/1/1988 - 6/30/1990

Claim for 493 ICD-9 codes related to MSK conditions

Low back conditions/Any

9

10 % sample with claim related to ICD-9 codes

NR

2,000,000a/396,000a/7,880

Stano [26]

1993

National/Fee for service

Claims/MEDSTAT

7/1/1988 - 6/30/1990

1. Claim for 493 ICD-9 codes related to MSK conditions, or 2. Claim for chiropractic care

Low back conditions/Any

4

Claim related to ICD-9 codes

1. Did not meet deductibles; 2. Did not file claims; 3. Out-of-plan use; 4. Elderly

2,000,000a/396,000a/10,945

  1. anumber reported as estimated
  2. bas reported in separate study, 70 % participated for 36 months and 30 % participated for 60 months [64]
  3. cinsured n and eligible n reported only for studies based on claims. Insured n refers to size of insured population. Eligible n refers to size of insured population meeting stated eligibility criteria
  4. drefers to the number of episodes of spine pain (i.e. members could have multiple episodes)
  5. eas reported in separate study [65]
  6. CPT current procedural terminology, DC doctor of chiropractic, DO doctor of osteopathy, ED emergency department, HMO health maintenance organization, ICD International Classification of Diseases, LBP low back pain, MD medical doctor, MSK musculoskeletal, NA not applicable, NR not reported, RAND Research and Development Corporation