Table 4.
Summary of HRR Variation in Chemotherapy Use
| Models | ||||
|---|---|---|---|---|
| [1] | [2] | [3] | [4] | |
| χ2 | ||||
| HRR indicator variables | 146 | 168 | 149 | |
| HRR characteristics | 47 | |||
| p-value | <.001 | <.001 | <.001 | <.001 |
| Control variables added | ||||
| Medical: age, stage, comorbidities, time | No | Yes | Yes | Yes |
| SES: race, education, income | No | No | Yes | Yes |
| ω statistics at the patient level (95% Ci) | ||||
| HRR versus medical* | — | 0.066 | 0.066 | 0.026 |
| (0.0481, 0.091) | (0.046, 0.093) | (0.014, 0.046) | ||
| HRR versus (medical+SES)* | — | — | 0.062 | 0.024 |
| (0.044, 0.087) | (0.014, 0.042) | |||
| HRR versus SES* | — | — | 1.610 | 0.557 |
| (0.092, 2.821) | (0.294, 1.055) | |||
| SES versus medical | — | — | 0.041 | 0.046 |
| (0.024, 0.068) | (0.037, 0.057) | |||
| ω statistics at the HRR level (95% CI) | ||||
| HRR versus medical* | — | 6.164 | 6.186 | 1.776 |
| (3.315, 11.461) | (3.362, 11.381) | (0.963, 3.274) | ||
| HRR versus (medical+SES)* | — | — | 2.972 | 0.819 |
| (1.526, 5.787) | (0.489, 1.370) | |||
| Household income | — | — | 7.026 | 1.799 |
| (2.765, 17.856) | (0.916, 3.529) | |||
| SES versus medical | — | — | 0.880 | 0.987 |
| (0.393, 1.970) | (0.739, 1.319) | |||
*
HRR refers to HRR characteristics for Models [1]–[3], and HRR characteristics for Model [4].
HRR, health referral region; SES, socioeconomic status.