PeriopSim™ instrument trainer
Figure 3 shows performance gains for Group A (compared with Group C) over three sessions of using PeriopSim™ Instrument Trainer. Repeated-measures ANOVA demonstrated a main effect of total scores, with a significant difference across the three training sessions (p < 0.0005). Post hoc tests (Bonferroni corrected) revealed that the total score on the PeriopSim™ Instrument Trainer increased significantly from session 1 to session 2 (10937 ± 1289 vs. 17029 ± 1427, respectively, p = 0.008). By session 3, Group A residents achieved a mean score of 21264 ± 873, which was significantly different from session 1 (p < 0.0005) and session 2 (p = 0.002) total scores (Fig. 3a).
Number of errors also differed significantly between three training sessions for Group A (p =0.013; Fig. 3b). Errors in identification of surgical instruments decreased from session 1 to session 2 (2.8 ± 0.9 vs. 0.8 ± 0.8), but this change was not statistically significant (p = 0.189). There was a significant drop in the number of errors between session 1 and session 3 (p = 0.046).
Group A residents saved time in the testing sessions by anticipating instruments while using the PeriopSim™ Instrument Trainer (Fig. 3c). There were additional savings in time with each repetition of the simulation: between session 1 and session 2 (p = 0.007) as well as between session 2 and session 3 (p = 0.002). By the third session, residents had doubled their saved time during simulation compared with their initial session.
The results demonstrated that the score, number of errors and time saved for Group C was not significantly different between the two testing sessions. As Group C was used to establish expert level performance, we also compared Group A’s performance to Group C. By the second session, Group A’s total score, number of errors, and time saved were not different from Group C.
PeriopSim™ for burr hole surgery
Group A and Group B performed PeriopSim™ in a simulated Burr Hole Surgery over three consecutive sessions (Fig. 2). Figure 4 shows how the groups performed.
In Group A, PeriopSim™ for Burr Hole Surgery total scores showed a significant increase between session 1 and session 2 (3703 ± 269 vs. 7062 ± 975, p = 0.037), but not between session 2 and session 3 (p = 0.136; Fig. 4a). The decrease in the number of errors for Group A was not significantly different between session 1 and session 2 (3.7 ± 0.7 vs. 2.1 ± 0.7, p = 0.548) or between session 2 and session 3 (p = 0.815; Fig. 4b).
Group A showed an increase in the time saved from session 1 to session 3 (5.4 ± 1 vs. 33.4 ± 8 sec.), which was statistically significant (p = 0.032). However, the difference in time saved was not significant from session 1 to session 2 (p = 0.055) or session 2 to session 3 (p = 0.156; Fig. 4c).
In Group B, PeriopSim™ for Burr Hole Surgery showed similar results to that of Group A. There was a significant increase in total scores between session 1 and session 2 performance (2767 ± 123 vs. 6565 ± 724, p = 0.002) and also between session 2 and session 3 (p = 0.005; Fig. 4a). The decrease in the number of errors was not significantly different over the three sessions (Fig. 4b).
As was seen in Group A, Group B demonstrated significant additional savings in time with each repetition of the simulated surgery. Time saved from session 1 to session 2 (1.3 ± 0.5 vs. 18.7 ± 3.7 sec.) was statistically significant (p = 0.005) and time saved from session 2 to session 3 was also significant (p = 0.005).
We compared the performance of trainees from Group B to those of Group A who had performed PeriopSim™ Instrument Trainer prior to PeriopSim™ for Burr Hole Surgery. Although the absolute numbers of errors were greater in Group B during session 1 (Fig. 4b), this difference was not statistically significant. With the exception of total score (p = 0.006) and time saved in session 1 (p = 0.008), there were no significant differences in performance between Group A and Group B.
As one might expect, Group C’s expert performance in PeriopSim™ for Burr Hole Surgery was not different over the testing sessions. By session 2, the mean score, number of errors, and time saved was not significantly different between the non-experts (Groups A and B) versus the experts (Group C).