Table 2.
Means and frequencies of each predictor variable in each sample in order of model entry
| All figures are n (%) unless otherwise indicated | Chronic Low Back Pain (n = 852) | Chronic Neck Pain (n = 705) | p-value for difference between groups |
|---|---|---|---|
| Mean (SD) # chiropractic visits/month | 2.3 (2.2) | 2.3 (2.0) | .900 |
| Enabling factors | |||
| Some insurance coverage for chiropractic | 590 (69.2%) | 475 (67.4%) | .520 |
| Unknown insurance coverage | 44 (5.2%) | 28 (4.0%) | |
| Need factors – pain characteristics | |||
| Rating of pain past 7 days (0–10), mean (SD) | 3.7 (2.1) | 4.0 (2.1) | .004 |
| Oswestry or Neck Disability Index score (0–100), mean (SD) | 20.5 (12.5) | 22.6 (12.5) | .001 |
| Have both CLBP and CNP | 444 (52.1%) | 428 (60.7%) | .001 |
| Years of pain | .278 | ||
| Less than 1 year | 107 (12.6%) | 80 (11.3%) | |
| 1 year to less than 2 years | 58 (6.8%) | 38 (5.4%) | |
| 2 years to less than 5 years | 115 (13.5%) | 112 (15.9%) | |
| 5 years to less than 10 years | 134 (15.7%) | 133 (18.9%) | |
| 10+ years | 418 (49.1%) | 324 (46.0%) | |
| Unknown | 20 (2.3%) | 18 (2.6%) | |
| Need factors – lifestyle and point in care | |||
| No heavy labor | 401 (47.1%) | 375 (53.2%) | .063 |
| Non-workday heavy labor: > 0% but < 20% | 108 (12.7%) | 68 (9.6%) | |
| Workday heavy labor: > 0% but < 20% | 163 (19.1%) | 140 (19.9%) | |
| Non-workday heavy labor: > 20% | 30 (3.5%) | 15 (2.1%) | |
| Workday heavy labor: > 20% | 87 (10.2%) | 58 (8.2%) | |
| Heavy labor: missing | 63 (7.4%) | 49 (7.0%) | |
| New patient (< 30 days) | 94 (11.0%) | 73 (10.4%) | .763 |
| Unknown time with this chiropractor | 145 (17.0%) | 113 (16.0%) | |
| Ended care during study period | 57 (6.7%) | 29 (4.1%) | 0.027 |
| Perceived need factors – goals for treatment | .001 | ||
| Goal: prevent pain getting worse | 120 (14.1%) | 84 (11.9%) | |
| Goal: prevent pain coming back; prevent reinjury | 178 (20.9%) | 107 (15.2%) | |
| Goal: ease or make pain go away temporarily | 268 (31.5%) | 290 (41.1%) | |
| Goal: make pain go away permanently | 276 (32.4%) | 218 (30.9%) | |
| Goal: other or missing | 10 (1.2%) | 6 (0.9%) | |
| Perceived need factors – pain beliefs | |||
| Believe their pain is chronic | 572 (67.1%) | 474 (67.2%) | .967 |
| What pain would be if didn’t see chiropractor 0–10, mean (SD) | 6.8 (2.3) | 6.9 (2.2) | .179 |
| Chronic pain will never go away: agree/strongly agree | 235 (27.6%) | 198 (28.1%) | <.001 |
| Important to understand causes of pain: agree/strongly agree | 801 (94.0%) | 669 (94.9%) | .452 |
| Unsafe to be physically active: agree/strongly agree | 53 (6.2%) | 25 (3.5%) | .016 |
| Perceived need factors – other psychological influences | |||
| Pain management self-efficacy (0–10), mean (SD) | 7.5 (1.8) | 7.7 (1.7) | .061 |
| Expect chiropractic very-extremely successful | 611 (71.7%) | 542 (76.9%) | .021 |
| Expect a lot to quite a bit of improvement | 538 (63.1%) | 447 (63.4%) | .916 |
| Worry about pain: mod to all the time | 152 (17.8%) | 116 (16.5%) | .471 |
| Has depression according to PROMIS items | 215 (25.2%) | 188 (26.7%) | .521 |
| Catastrophizing (0–12 scale), mean (SD) | 2.3 (2.3) | 2.2 (2.3) | .389 |
| Predisposing factors | |||
| Age in years | 48.5 (14.9) | 45.8 (13.2) | <.001 |
| Female | 558 (65.5%) | 579 (82.1%) | <.001 |
| Education: At least a 4-year degree | 462 (54.2%) | 413 (58.6%) | .085 |
| Chiropractor practice characteristics | |||
| Average number of patients treated per day | 25.3 (12.8) | 25.6 (12.3) | .612 |
| Percentage of patients on preventive/maintenance | 23.7 (17.3) | 24.1 (17.4) | .660 |
| In practice 5 to 10 years | 100 (11.7%) | 84 (11.9%) | .598 |
| In practice > 10 to 20 years | 268 (31.5%) | 222 (31.5%) | |
| In practice > 20 to 30 years | 258 (30.3%) | 231 (32.8%) | |
| In practice > 30 years | 226 (26.5%) | 168 (23.8%) | |
| Clinic location is urban (> 50,000 population) | 541 (63.5%) | 477 (67.7%) | .086 |
| Average number of physical modalities used | 3.3 (1.4) | 3.2 (1.4) | .849 |
| College from which chiropractor graduated | .344 | ||
| Life College | 79 (9.3%) | 63 (8.9%) | |
| National College of Chiropractic [fix order later] | 46 (5.4%) | 42 (6.0%) | |
| Los Angeles College of Chiropractic | 28 (3.3%) | 29 (4.1%) | |
| New York Chiropractic College | 90 (10.6%) | 54 (7.7%) | |
| Northwestern Chiropractic College | 212 (24.9%) | 199 (28.2%) | |
| Palmer Chiropractic College | 106 (12.4%) | 94 (13.3%) | |
| Parker Chiropractic College | 73 (8.6%) | 45 (6.4%) | |
| Texas Chiropractic College | 81 (9.5%) | 58 (8.2%) | |
| University of Western States | 106 (12.4%) | 97 (13.8%) | |
| Other | 31 (3.6%) | 24 (3.4%) | |
| State/Region | .038 | ||
| California | 130 (15.3%) | 125 (17.7%) | |
| Florida | 71 (8.3%) | 56 (7.9%) | |
| Minnesota | 208 (24.4%) | 199 (28.2%) | |
| New York | 155 (18.2%) | 99 (14.0%) | |
| Oregon | 117 (13.7%) | 111 (15.7%) | |
| Texas | 171 (20.1%) | 115 (16.3%) | |