Results
There were 366 surgeons who performed 43,604 isolated CABG that met the inclusion criteria for our study (Table 1). Of these, 252 surgeons operated in California and 114 operated in New York. The median number of years-in-practice was 20 (interquartile range [IQR] 11-28) and the median O:E ratio for isolated CABG was 0.87 (IQR 0.19-1.4). Years in practice was roughly normally distributed. The median EMR and case volume for California surgeons were 2.42 (IQR 1.76, 2.95) and 78.5 (IQR 32.25-129.5) respectively. For New York surgeons median EMR and case volume were 1.44 (IQR 1.22, 1.68) and 158 (IQR 87.75-243.5).
Linear regression relating normalized EMR to years in practice did not show a statistically significant relationship, with similar EMR across the number of years in practice (Table 2). This trend was also visually summarized using Loess regression (Figure 1). A sensitivity analysis in which surgeons with <25 cases were excluded to determine if these surgeons were skewing the data also showed no statistically significant relationship between years in practice and EMR (Table 3). Lastly, linear regression relating surgeon isolated CABG O:E ratio to years in practice, with adjustment for surgeon case volume, also showed no statistically significant relationship with similar O:E ratios across the number of years in practice (Table 4). This trend was also visually summarized using Loess regression (Figure 2).