Table 6. Unadjusted Analyses of the Total Number of General Payments per Physician in 2015.
| Mean No. of Payments per Physician (95% CI) | Absolute Difference, No. (95% CI) | IRR (95% CI)a,b | |
|---|---|---|---|
| Specialty category | |||
| Surgery | 13.2 (13.0 to 13.3) | −14.5 (−14.8 to −14.2) | 0.90 (0.89 to 0.90) |
| Primary care | 27.7 (27.5 to 27.9) | 0 [Reference] | 1 [Reference] |
| Specialists | 19.5 (19.2 to 19.8) | −8.2 (−8.5 to −7.8) | 0.82 (0.82 to 0.83) |
| Interventionalists | 28.8 (28.4 to 29.2) | 1.1 (0.7 to 1.6) | 1.09 (1.09 to 1.10) |
| Sex | |||
| Men | 25.3 (25.1 to 25.4) | 8.2 (7.9 to 8.5) | 1.20 (1.19 to 1.20) |
| Women | 17.0 (16.8 to 17.2) | 0 [Reference] | 1 [Reference] |
| Practice spending region | |||
| Low | 17.0 (16.7 to 17.3) | −6.3 (−6.7 to −5.9) | 0.83 (0.82 to 0.84) |
| Average | 23.3 (23.1 to 23.5) | 0 [Reference] | 1 [Reference] |
| High | 24.4 (24.1 to 24.7) | 1.1 (0.8 to 1.4) | 1.04 (1.03 to 1.05) |
| Sole proprietor status | |||
| No | 23.1 (22.9 to 23.2) | 0 [Reference] | 1 [Reference] |
| Yes | 22.5 (22.3 to 22.8) | −0.6 (−0.9 to −0.2) | 0.98 (0.98 to 0.99) |
| No response | 18.7 (18.1 to 19.3) | −4.4 (−5.0 to −3.7) | 0.88 (0.87 to 0.89) |
Abbreviation: IRR, incidence rate ratio.
a
The incidence rate ratio represents the exponent of the log of annual per-physician number of payments compared with the reference group.
b
The statistical test via generalized unadjusted negative binomial regression model was significant after Bonferroni correction for multiple comparisons (P < .001, 2-sided P value; all tests).