Table 3. Unconditional logistic regression analyses of a physician in the ambulance car and outcome among patients with OHCA.
| ROSC | 1-mo survival | CPC (1 or 2) | OPC (1 or 2) | |||||
| OR (95% CI) | p | OR (95% CI) | p | OR (95% CI) | p | OR (95% CI) | p | |
| Unadjusted | ||||||||
| Total (n = 619,928) | 4.65 (4.48–4.82) | <0.001 | 2.39 (2.28–2.51) | <0.001 | 2.43 (2.27–2.59) | <0.001 | 2.44 (2.28–2.61) | <0.001 |
| 3-member ambulance crew (n = 603,493)a | 3.54 (2.96–4.24) | <0.001 | 1.58 (1.20–2.06) | <0.01 | 1.70 (1.18–2.44) | <0.01 | 1.71 (1.19–2.47) | <0.01 |
| Excluded cases, in which physician did ALSb but did not ride in ambulance car (n = 538,913) | 4.67 (4.50–4.84) | <0.001 | 2.40 (2.28–2.52) | <0.001 | 2.42 (2.26–2.58) | <0.001 | 2.43 (2.27–2.60) | <0.001 |
| Adjusted for selected variablesc | ||||||||
| Total (n = 609,865) | 3.60 (3.46–3.74) | <0.001 | 1.59 (1.51–1.68) | <0.001 | 1.37 (1.27–1.48) | <0.001 | 1.38 (1.28–1.48) | <0.001 |
| 3-member ambulance crew (n = 593,512)a | 3.54 (2.96–4.24) | <0.001 | 1.07 (0.80–1.43) | 0.63 | 1.02 (0.69–1.51) | 0.93 | 1.03 (0.70–1.53) | 0.87 |
| Excluded cases, in which physician did ALSb but did not ride in ambulance car (n = 530,633) | 3.61 (3.47–3.75) | <0.001 | 1.58 (1.50–1.66) | <0.001 | 1.35 (1.25–1.45) | <0.001 | 1.36 (1.26–1.46) | <0.001 |
| Adjusted for all covariatesd | ||||||||
| Total (n = 569,793) | 2.66 (2.54–2.79) | <0.001 | 0.91 (0.85–0.97) | <0.01 | 0.80 (0.73–0.88) | <0.001 | 0.82 (0.74–0.90) | <0.001 |
| 3-member ambulance crew (n = 554,019)a | 2.02 (1.63–2.50) | <0.001 | 0.65 (0.47–0.91) | <0.05 | 0.51 (0.33–0.79) | <0.01 | 0.52 (0.34–0.81) | <0.01 |
| Excluded cases, in which physician did ALSb but did not ride in ambulance car (n = 498,223) | 1.90 (1.75–2.07) | <0.001 | 1.11 (0.98–1.25) | 0.11 | 1.11 (0.95–1.31) | 0.20 | 1.11 (0.94–1.31) | 0.20 |
OR: odds ratio; CI: confidence interval.
a: Cases for which both an emergency life-saving technician (ELST) and a physician (MD) were in the ambulance car were excluded.
b: Advanced life support.
c: Selected variables included age, sex, bystander eyewitness, relationship of bystander to patient, bystander chest compression, bystander rescue breathing, use of public-access AED by bystander, first documented rhythm, and time from call to arrival at the scene for a model with ROSC as a dependent variable. As for other models, ROSC and the above selected variables were adjusted.
d: All covariates included all variables except for endpoint variables listed in Table 1 plus 46 dummy variables for the 47 prefectures in Japan for a model with ROSC as a dependent variable. As for other models, ROSC, all variables except for endpoint variables listed in Table 1, and 46 dummy variables for the 47 prefectures in Japan were adjusted.