# Using Virtual Reality Simulators to Enhance Laparoscopic Cholecystectomy Skills Learning
## 3 Results
### Meta-Analysis  
A total of 10 RCT experiments were included in the meta-analysis involving participants' performance in the VRT group compared with that in the control training group (no additional training). For experiments comparing benchmark VRT with other interventions, the benchmark VRT group was treated as the control group. Studies were excluded when only median values were reported, and reconstruction attempts were made using the method described in Section 2.5. \begin{table}
\begin{tabular}{c c c c c c c c c c} \hline \hline  
The meta-analysis for the time to completion fell in favor of VRT, as is shown in Table 2. The weighted mean difference in time to completion for VRT compared with traditional training was \(-0.24\) with \(95\%\) confidence intervals (CI) of \(-0.32\) and \(-0.16\). The results indicated that the intervention groups completed the tasks \(24\%\) faster than the control groups. Participants with VRT outperformed participants with no additional training or traditional training. It also showed that VRT with a deliberately designed curriculum could improve skill level significantly. We also explored the difference in performance improvement of medical students and residents (Table 3). Surprisingly, the results showed that the residents subgroup achieved a \begin{table}
\begin{tabular}{c c c c c c c c c c c c c c c} \hline \hline  & \multicolumn{3}{c}{**Intervention**} & \multicolumn{3}{c}{**Control**} & \multicolumn{3}{c}{**Mean Difference**} & \multicolumn{3}{c}{**Weight**} & \multicolumn{3}{c}{**Mean Difference**} \\ \hline
**Study** & **Mean** & **S.D.** & **N** & **Mean** & **S.D.** & **N** & **IVhet, 95\% CI** & **(\%)** & **IVhet, 95\% CI** \\ \hline VR vs. NAT subgroup & & & & & & & & & & & & & \\ [PERSON] et al. [27] & 0.80 & 0.49 & 20 & 1.00 & 0.55 & 20 & \(-0.20\) [\(-0.53\), \(0.12\)] & 5.51 & & & & & \\ [PERSON] et al. [31] & 0.73 & 0.31 & 33 & 1.00 & 0.40 & 31 & \(-0.27\) [\(-0.45\), \(-0.10\)] & 18.48 & & & & & \\ [PERSON] et al. [45] & 0.70 & 0.22 & 8 & 1.00 & 0.27 & 8 & \(-0.30\) [\(-0.60\), \(-0.15\)] & 6.50 & & & & & & \\ Subtotal & & & & & & & & & & & & & & \\  & & & & & & & & & & & & & & \\  & & & & & & & & & & & & & & \\ \hline VR vs. TT subgroup & & & & & & & & & & & & & & \\ [PERSON] et al. (13) [37] & 0.80 & 0.21 & 10 & 1.00 & 0.23 & 10 & \(-0.20\) [\(-0.39\), \(0.00\)] & 15.09 & & & & & & \\ \hline VR+ vs. VR subgroup & & & & & & & & & & & & & & \\ [PERSON] et al. [34] & 0.95 & 0.56 & 7 & 1.00 & 0.55 & 7 & \(-0.05\) [\(-0.63\), \(0.53\)] & 1.73 & & & & & & \\ von [PERSON] et al. [36] & 0.76 & 0.34 & 107 & 1.00 & 0.38 & 81 & \(-0.24\) [\(-0.35\), \(-0.14\)] & 52.69 & & & & & & \\  & & & & & & & & & & & & & & \\  & & & & & & & & & & & & & & \\  & & & & & & & & & & & & & & & \\ \hline Overall & & & & & & & & & & & & & & & \\  & & & & & & & & & & & & & & & \\  & & & & & & & & & & & & & & & \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Forest plot for the time to completion of task, Virtual Reality (VR), No Additional Training (NAT), Traditional Training (TT), and Virtual Reality with feedback (VR+). Figure 2: Risk of bias: (**a**) individual studies, (**b**) summary of all the studies. 25% time reduction, while the medical students group achieved 20%. It indicated that the VR simulators in the market benefit both novices and participants with experience. The realism and the complexity of VR training tasks allow for significant improvement of skill level, even for participants with experience. The meta-analysis for the performance scores fell in favor of VRT in general. As is shown in Table 4, the weighted mean difference in scores for VRT compared with traditional training was 2.92 with 95% confidence intervals (CI) of 0.96 and 4.88, on our standardized scale of 1-10. The results showed that, on average, the intervention groups scored 29.2% higher than the control groups. Similarly to time-to-completion results, we also observed that participants with VRT with a deliberately designed curriculum outperformed participants with basic VRT.