Table 3 Spearman rank correlation coefficients and areas under ROC curves showing agreement between objective and subjective assessments of image quality
From: Patient-specific optimisation of administered activity and acquisition times for 18F-FDG PET imaging
Objective measure | Spearman rank correlation coefficient | Area under the ROC curve for identifying images which are “definitely adequate” or better | ||||
|---|---|---|---|---|---|---|
Value | 95% confidence interval | p value for difference from NECpatient | Value | 95% confidence interval | p value for difference from NECpatient | |
SNRliver | 0.74 | 0.68–0.78 | 0.43 | 0.90 | 0.86–0.93 | 0.03 |
SNRAA | 0.60 | 0.52–0.66 | <0.01 | 0.82 | 0.77–0.86 | <0.01 |
NECpatient | 0.77 | 0.72–0.81 | 0.94 | 0.91–0.96 | ||
NECdensity | 0.73 | 0.68–0.78 | 0.35 | 0.91 | 0.88–0.94 | 0.01 |