Table 4

Key Findings Regarding Influence of Initial Provider on Primary and Secondary Health Care Outcomesa
Category Study Health Care Outcomes per Episode of Care
Care seekingCarey et al (1995)Mean no. of visits associated with initiation of care significantly higher with DCs than with medical providers (mean visits in rural/urban areas = 10.1/15 for DCs vs 4.6/4.4 for PCPs; P = .001)
Sundararajan et al (1998)Patients who saw HMO providers least likely to see multiple providers during an episode of care for LBP (9% [95% CI = 5% to 14%]), whereas patients who initiated care with orthopedic surgeons most likely to do so (30% [95% CI = 23% to 37%]); of those who initiated care with DCs and PCPs, 19% (95% CI = 16% to 23%) and 14% (95% CI = 11% to 17%), respectively, sought care from other health care providers
Fritz et al (2016)Duration of episode of care with initial visit in DC setting longer than that with initial visit in primary care setting (standardized ß = 0.51 [95% CI = 0.27 to 0.76]; P < .001)

Medication use/prescriptionCarey et al (1995)Average no. of prescriptions or over-the-counter medications lower among patients initiating care with DCs than among those initiating care with medical practitioners (2.3 vs 3.5 medications, respectively; P < .001)
Fritz et al (2015)Odds of receiving opioid medication early significantly lower for patients entering via physical therapy (OR = 0.5 [95% CI = 0.28 to 0.89]; P = .02) than for those entering via primary care (combined PCP, ED, and physiatry)
Frogner et al (2018)Patients who had physical therapy first had an 89.4% (SE = 0.053; P < .001) reduced probability of receiving an opioid prescription than those who had no physical therapy or physical therapy later
Azad et al (2019)Compared with patients who initiated care with PCP, those who initiated care with nonmedical provider less likely to receive an early opioid prescription (HR = 0.5 [95% CI = 0.49 to 0.5]; P < .0001) and less likely to receive a third opioid prescription (HR = 0.45 [95% CI = 0.43 to 0.46]; P < .0001)
Kazis et al (2019)Compared with patients who initiated care with PCP, patients who initiated care with DC (OR = 0.1 [95% CI = 0.09 to 0.1]; P < .01), acupuncturist (OR = 0.09 [95% CI = 0.07 to 0.12]; P < .01), or physical therapist (OR = 0.15 [95% CI = 0.13 to 0.17]; P < .01) had significantly lower odds of early opioid use; this result also seen with long-term opioid use (for DC: OR = 0.22 [95% CI = 0.15 to 0.48] [P < .01]; for acupuncturist: OR = 0.07 [95% CI = 0.01 to 0.48] [P < .01]; for physical therapist: OR = 0.27 [95% CI = 0.15 to 0.48] [P < .01])

ImagingCarey et al (1995)No. of radiographs higher per episode of care for patients initiating care with DCs and orthopedic surgeons (67%–72% of patients) than for those initiating care with PCPs (26%–32% of patients) (P = .001); use of advanced imaging lower for patients seeing DCs (7%–8%) and going to HMO (6%) than for patients seeing an orthopedist (17%) (P = .004)
Fritz et al (2015)Relative to primary care, physical therapy as entry setting associated with lower odds of radiography (OR = 0.32 [95% CI = 0.15 to 0.65]; P < .001); no statistical difference seen in advanced imaging rates
Fritz et al (2016)Relative to primary care, physical therapy as entry setting associated with decreased risk of radiography (OR = 0.39 [95% CI = 0.18–0.84]), but no statistical difference in advanced imaging rates; chiropractic as entry setting associated with decreased risk of advanced imaging rates (OR = 0.21 [95% CI = 0.08 to 0.50]), but no statistical difference in radiography
Frogner et al (2018)Patients who had physical therapy as first point of care had 29.7% (SE = 0.045; P < .001) reduced probability of having advanced imaging and 16.6% (SE = 0.056; P < .001) reduced probability of having radiography than those who had no physical therapy or physical therapy later
O’Reilly-Jacob et al (2019)No significant difference in rates of low-value back images between primary care medical doctors (24.5% [IQR = 11%–38%]) and primary care nurse practitioners (26.5% [IQR = 7%–40%]) after initial consultation

Cost of careCarey et al (1995)Care initiated by urban chiropractors (adjusted mean = $783 [95% CI = $698 to $868]) and orthopedists (adjusted mean = $746 [95% CI = $633 to $858]) had highest costs per episode of LBP compared with care initiated via urban primary care providers (adjusted mean = $508 [95% CI = $418 to $598])
Liliedahl et al (2010)Mean cost per episode significantly lower for care initiated with chiropractor ($532.54 [SE = $9.56]) than initiated with medical doctor ($661.10 [SE = $29.16])
Fritz et al (2015)Physical therapy as entry point of care associated with significantly lower health care costs over 12 mo ($335 [95% CI = $241 to $429]) than primary care ($533 [95% CI = $470 to $598])
Fritz et al (2016)Care initiated via physical therapy (standardized ß = −0.21 [95% CI = −0.63 to 0.2]; P = .34) and chiropractic (standardized ß = −0.28 [95% CI = −0.058 to 0.021]; P = .07) not associated with statistically significant differences in cost compared with care initiated via primary care
Frogner et al (2018)Care initiated via physical therapy associated with higher provider costs but lower pharmacy, outpatient, and out-of-pocket costs than care not initiated via physical therapy; total costs did not differ between patients who did and patients who did not initiate care via physical therapy
Garrity et al (2020)The 90-d cost ratio higher for care initiated via physical therapy in both provisional access states (1.28 [95% CI = 1.20 to 1.36]) and unrestricted states (1.14 [95% CI = 1.05 to 1.23]) than for care initiated via primary care
(continued on Tanle 4B)