Table 2 Comparison of trainee performance in AR-US and S-US groups for CVC placement
| Â | AR-US, seconds | S-US, seconds | Mean difference (95% CI) | p-value |
|---|---|---|---|---|
T1 (N) | Mean (SD) | Mean (SD) | Â | Â |
 All (47) | 22.21 (17.77) | 25.11 (25.51) | -2.90 (-11.91, 6.13) | 0.53 |
 UGY (22) | 21.77 (15.94) | 31.05 (34.92) | -9.28 (-26.00, 7.45) | 0.27 |
 PGY (25) | 22.60 (19.56) | 19.88 (10.94) | 2.72 (-6.36, 11.80) | 0.55 |
 Male (32) | 25.66 (19.89) | 27.75 (29.95) | -2.09 (-14.84, 10.65) | 0.74 |
 Female (15) | 14.87 (8.75) | 19.47 (10.10) | -4.60 (-11.67, 2.47) | 0.19 |
T2 (N) | Mean (SD) | Mean (SD) | Â | Â |
 All (47) | 38.19 (25.54) | 52.32 (59.60) | -14.13 (-33.03, 4.78) | 0.14 |
 UGY (22) | 37.59 (15.86) | 46.50 (34.82) | -8.91 (-25.59, 7.77) | 0.28 |
 PGY (25) | 38.72 (32.08) | 57.44 (75.42) | -18.72 (-52.09, 14.65) | 0.26 |
 Male (32) | 37.06 (20.30) | 55.44 (66.74) | -18.38 (-43.37, 6.62) | 0.14 |
 Female (15) | 40.60 (34.94) | 45.67 (41.70) | -5.07 (-33.88, 23.71) | 0.72 |
TU (N) | Mean (SD) | Mean (SD) | Â | Â |
 All (47) | 60.40 (32.82) | 77.43 (67.67) | -17.03 (-38.92, 4.88) | 0.13 |
 UGY (22) | 59.36 (24.86) | 77.55 (60.01) | -18.19 (-46.55, 10.19) | 0.20 |
 PGY (25) | 61.32 (39.01) | 77.32 (75.01) | -16.00 (-50.29, 18.29) | 0.35 |
 Male (32) | 62.72 (29.14) | 83.19 (76.80) | -20.47 (-49.82, 8.88) | 0.17 |
 Female (15) | 55.47 (40.26) | 65.13 (41.83) | -9.66 (-40.37, 21.04) | 0.52 |
TNU (N) | Mean (SD) | Mean (SD) | Â | Â |
 All (47) | 130.70 (53.64) | 130.00 (53.01) | 0.70 (-21.12, 22.57) | 0.95 |
 UGY (22) | 140.05 (56.11) | 146.05 (49.96) | -6.00 (-38.32, 26.32) | 0.71 |
 PGY (25) | 122.50 (51.09) | 115.84 (52.50) | 6.66 (-22.82, 36.10) | 0.65 |
 Male (32) | 134.44 (59.55) | 123.50 (53.09) | 10.94 (-17.26, 39.13) | 0.44 |
 Female (15) | 122.73 (38.76) | 143.80 (51.86) | -21.07 (-55.31, 13.17) | 0.22 |