Table 1.
Baseline characteristics.
| Before matching | After matching | |||||
|---|---|---|---|---|---|---|
| Variable (n (%) or mean (SD)) | SMT | Non‐SMT | SMD | SMT | Non‐SMT | SMD |
| N | 3118 | 141,039 | NA | 3116 | 3116 | NA |
| Demographics | ||||||
| Age at Index | 47.8 (16.9) | 47.6 (16.2) | 0.013 | 47.9 (16.9) | 47.8 (16.4) | 0.004 |
| Female | 2375 (76%) | 101207 (72%) | 0.101 | 2373 (76%) | 2385 (77%) | 0.009 |
| Male | 743 (24%) | 33568 (24%) | 0.001 | 743 (24%) | 729 (23%) | 0.011 |
| Hispanic or Latino | 65 (2%) | 18609 (13%) | 0.428 | 65 (2%) | 67 (2%) | 0.004 |
| Not Hispanic or Latino | 2708 (87%) | 93309 (66%) | 0.503 | 2706 (87%) | 2712 (87%) | 0.006 |
| American Indian or Alaska Native | 16 (1%) | 406 (< 1%) | 0.036 | 16 (1%) | 12 (< 1%) | 0.019 |
| Asian | 26 (1%) | 5795 (4%) | 0.212 | 26 (1%) | 27 (1%) | 0.003 |
| Black or African American | 125 (4%) | 25736 (18%) | 0.465 | 125 (4%) | 119 (4%) | 0.010 |
| Native Hawaiian or Other Pacific Islander | 10 (< 1%) | 882 (1%) | 0.044 | 10 (< 1%) | 10 (< 1%) | 0.000 |
| White | 2548 (82%) | 83227 (59%) | 0.513 | 2546 (82%) | 2525 (81%) | 0.017 |
| Other Race | 37 (1%) | 6272 (4%) | 0.198 | 37 (1%) | 48 (2%) | 0.030 |
| Diagnoses | ||||||
| Adverse socioeconomic circumstances | 62 (2%) | 6997 (5%) | 0.163 | 62 (2%) | 65 (2%) | 0.007 |
| Anxiety‐related disorders | 982 (31%) | 43225 (31%) | 0.018 | 981 (31%) | 988 (32%) | 0.005 |
| Cervicalgia | 1580 (51%) | 21068 (15%) | 0.823 | 1578 (51%) | 1609 (52%) | 0.020 |
| Chronic pain, not elsewhere classified | 615 (20%) | 21101 (15%) | 0.126 | 615 (20%) | 629 (20%) | 0.011 |
| Diseases of the digestive system | 1237 (40%) | 57994 (41%) | 0.029 | 1237 (40%) | 1231 (40%) | 0.004 |
| Mood disorders | 750 (24%) | 34154 (24%) | 0.004 | 749 (24%) | 724 (23%) | 0.019 |
| Nicotine dependence | 181 (6%) | 13978 (10%) | 0.153 | 181 (6%) | 179 (6%) | 0.003 |
| Overweight and obesity | 526 (17%) | 25437 (18%) | 0.031 | 526 (17%) | 501 (16%) | 0.022 |
| Psychoactive substance use | 265 (8%) | 19634 (14%) | 0.172 | 265 (9%) | 261 (8%) | 0.005 |
| Pregnancy, childbirth, and the puerperium | 215 (7%) | 8765 (6%) | 0.028 | 214 (7%) | 216 (7%) | 0.003 |
| Sleep disorders | 604 (19%) | 24306 (17%) | 0.055 | 604 (19%) | 588 (19%) | 0.013 |
| Tobacco use | 37 (1%) | 7922 (6%) | 0.246 | 37 (1%) | 41 (1%) | 0.012 |
| Prior treatments | ||||||
| Medication(s) (any) | 2881 (92%) | 129229 (92%) | 0.028 | 2879 (92%) | 2846 (91%) | 0.039 |
| Acetaminophen | 992 (32%) | 49214 (35%) | 0.065 | 991 (32%) | 937 (30%) | 0.037 |
| Antidepressants | 1218 (39%) | 44168 (31%) | 0.163 | 1216 (39%) | 1166 (37%) | 0.033 |
| Aspirin | 455 (15%) | 15822 (11%) | 0.101 | 453 (15%) | 435 (14%) | 0.017 |
| Benzodiazepines | 638 (20%) | 32124 (23%) | 0.056 | 638 (20%) | 652 (21%) | 0.011 |
| Butalbital | 45 (1%) | 11090 (8%) | 0.308 | 45 (1%) | 58 (2%) | 0.033 |
| Caffeine | 100 (3%) | 14042 (10%) | 0.275 | 100 (3%) | 115 (4%) | 0.026 |
| Ibuprofen | 672 (22%) | 27463 (19%) | 0.052 | 670 (22%) | 648 (21%) | 0.017 |
| Opioid analgesics | 902 (29%) | 48602 (34%) | 0.119 | 902 (29%) | 871 (28%) | 0.022 |
| Sedatives/hypnotics | 230 (7%) | 9026 (6%) | 0.039 | 230 (7%) | 233 (7%) | 0.004 |
| Skeletal muscle relaxants | 698 (22%) | 32402 (23%) | 0.014 | 698 (22%) | 672 (22%) | 0.020 |
| Chiropractic care* (spinal or extraspinal manipulation) | 2668 (86%) | 93 (0%) | 3.432 | 2666 (86%) | 57 (2%) | 3.148 |
Note: Reported for descriptive purposes only and not matched (*). Counts of 10 should be interpreted with caution as TriNetX rounds count 1–9 up to 10 for de‐identification purposes.
Abbreviation: SMD, Standardized mean difference.