TABLE 1.
Reproducibility and Reliability Based on the Manual Segmented CRSN of NM‐MRI Sequences
| GRE MT on | TSE MT on | TSE MT off | ||||
|---|---|---|---|---|---|---|
| CRSN‐RN | CRSN‐CC | CRSN‐RN | CRSN‐CC | CRSN‐RN | CRSN‐CC | |
| Mean CR% (SD) | ||||||
| Rater 1 (test) | 21.59 (2.26) | 21.64 (2.13) | 21.35 (2.32) | 13.51 (2.20) | 16.49 (2.96) | 9.04 (2.20) |
| Rater 1 (retest) | 22.89 (2.69) | 21.42 (2.15) | 20.90 (2.57) | 12.96 (2.07 | 16.27 (3.54) | 9.14 (2.13) |
| Rater 2 (test) | 20.86 (3.21) | 22.48 (2.18) | 19.63 (3.45) | 13.19 (2.25) | 16.29 (3.42) | 9.07 (2.21) |
| Rater 2 (retest) | 23.14 (2.80) | 21.75 (2.35) | 21.13 (2.15) | 12.87 (1.76) | 16.76 (2.68) | 8.98 (2.28) |
| Rater 3 (test) | 21.59 (2.86) | 19.72 (1.93) | 20.37 (3.05) | 12.14 (1.98) | 16.54 (2.42) | 7.73 (1.72) |
| Rater 3 (retest) | 22.28 (2.81) | 20.37 (2.10) | 20.63 (1.91) | 11.78 (2.01) | 16.69 (2.29) | 7.94 (1.88) |
| Raters combined (test) | 21.35 (2.74) | 21.28 (2.33) | 20.45 (2.97) | 12.95 (2.16) | 16.44 (2.87) | 8.61 (2.09) |
| Raters combined (retest) | 22.77 (2.71) | 21.18 (2.22) | 20.89 (2.17) | 12.54 (1.97) | 16.58 (2.80) | 8.69 (2.11) |
| Test–retest variability (SD) | ||||||
| Rater 1 | 7.47 (5.94) | 4.92 (2.58) | 7.35 (5.55) | 9.92 (7.38) | 12.83 (9.09) | 8.70 (9.23) |
| Rater 2 | 13.51 (9.72) | 5.98 (4.25) | 11.25 (11.30) | 7.41 (5.30) | 14.87 (12.38) | 15.68 (15.57) |
| Rater 3 | 7.86 (6.81) | 5.73 (4.23) | 8.65 (9.25) | 10.29 (9.18) | 8.84 (5.42) | 16.55 (9.39) |
| Test–retest ICC (95% CI) | ||||||
| Rater 1 | 0.74 (0.28–0.91) | 0.84 (0.51–0.95) | 0.70 (0.21–0.91) | 0.76 (0.32–0.93) | 0.73 (0.27–0.92) | 0.86 (0.55–0.96) |
| Rater 2 | 0.58 (0.05–0.87) | 0.79 (0.40–0.94) | 0.61 (0.05–0.88) | 0.85 (0.54–0.96) | 0.54 (–0.05–0.85) | 0.60 (0.04–0.88) |
| Rater 3 | 0.69 (0.19–0.91) | 0.79 (0.39–0.94) | 0.55 (–0.04–0.84) | 0.67 (0.15–0.90) | 0.75 (0.320–0.93) | 0.66 (0.13–0.89) |
| Rater ICC (95% CI) | ||||||
| Intrarater ICC (R1) | 0.94 (0.86–0.98) | 0.92 (0.80–0.97) | 0.80 (0.58–0.91) | 0.97 (0.92–0.99) | 0.86 (0.70–0.94) | 0.85 (0.68–0.94) |
| Intrarater ICC (R2) | 0.85 (0.68–0.94) | 0.88 (0.56–0.96) | 0.75 (0.46–0.89) | 0.75 (0.49–0.89) | 0.81 (0.58–0.92) | 0.87 (0.66–0.95) |
| Intrarater ICC (R3) | 0.93 (0.83–0.97) | 0.93 (0.83–0.97) | 0.55 (0.17–0.78) | 0.90 (0.79–0.96) | 0.86 (0.69–0.94) | 0.92 (0.72–0.97) |
| Interrater ICC | 0.75 (0.57–0.88) | 0.63 (0.22–0.84) | 0.65 (0.44–0.82) | 0.81 (0.45–0.93) | 0.62 (0.39–0.81) | 0.79 (0.44–0.92) |
Given are the test–retest variability for each rater and ICC values with 95% confidence interval.
SN: substantia nigra; CR: contrast ratio; CR%: contrast ratio * 100; SD: standard deviation; R1: rater 1; R2: rater 2; R3: rater 3; ICC: intraclass correlation coefficient; 95% CI: 95 percent confidence interval; GRE: gradient recalled echo; MT: magnetization transfer pulse; TSE: turbo spin echo.