Table 4.
Misclassification rate of physicians’ initial assessment of absolute risk for postoperative complications
| Intensive care unit admission greater than 48 hours | Acute kidney injury | Mechanical ventilation greater than 48 hours | Cardiovascular complications | Severe sepsis | Thirty-day mortality | |
|---|---|---|---|---|---|---|
| Misclassification rate | ||||||
| Physicians’ initial risk assessment | ||||||
| Overall | 37 (4) | 41 (0.04) | 43 (4) | 57 (4) | 63 (4) | 65 (4) |
| By physician’s specialty | ||||||
| Surgery | 38 (8) | 59 (8)* | 44 (8) | 69 (7) | 67 (8) | 77 (7) |
| Anesthesiology/Emergency Medicine | 37 (5) | 35 (5) | 42 (5) | 52 (5) | 61 (5) | 60 (5) |
| By training status | ||||||
| Attending physicians | 36 (5) | 38 (5) | 40 (5) | 52 (5) | 61 (5) | 61 (5) |
| Trainees | 41 (8) | 51 (8) | 49 (8) | 68 (7) | 68 (7) | 73 (7) |
| Correlation between years of practice and misclassification rate, r (p-value) | −0.13 (0.63) | −0.63 (0.01) | −0.27 (0.30) | −0.14 (0.60) | 0.03 (0.92) | −0.43 (0.09) |
Data represents proportion of misclassified cases as percent and its standard error in parenthesis. Correlation between years of practice and average misclassification rate for physicians was calculated using Spearman correlation.
A case was considered as misclassified if MySurgeryRisk algorithm risk score or physician’s assessment of absolute risk classified patient into low risk group for positive cases, where the complication was observed or into high risk group for negative cases, where the complication was not observed, Thresholds separating low and high-risk groups were 0.32 for Intensive care unit admission greater than 48 hours , 0.26 for acute kidney injury, 0.13 for mechanical ventilation greater than 48 hours, 0.07 for cardiovascular complications, 0.05 for severe sepsis, and 0.034 for 30-day mortality.
P< 0.05 using Fisher’s exact test. No significant difference (p>0.05) was observed in proportion of misclassified cases between attending physicians and trainees.