Characterization of high-grade prostate cancer at multiparametric MRI: assessment of PI-RADS version 2.1 and version 2 descriptors across 21 readers with varying experience (MULTI study)

Insights into Imaging

Table 2 Inter-reader agreement (analysis of the 240 predefined lesions)

		All readers	Experienced seniors	Less experienced seniors	Juniors
Lesion location (PZ, TZ or CZ) ⁽¹⁾		0.65 [0.59–0.70]	0.73 [0.67–0.79]	0.60 [0.54–0.65]	0.63 [0.55–0.69]
Lesion size ⁽²⁾		0.80 [0.75–0.86]	0.82 [0.76–0.88]	0.82 [0.76–0.88]	0.81 [0.76–0.87]
PI-RADSv2.1 categories	T2w ⁽³⁾	0.49 [0.45–0.52]	0.58 [0.54–0.62]	0.51 [0.46–0.55]	0.42 [0.38–0.46]
	Dw ⁽³⁾	0.51 [0.47–0.54]	0.57 [0.53–0.61]	0.52 [0.47–0.56]	0.48 [0.44–0.52]
	DCE ⁽¹⁾	0.30 [0.25–0.34]	0.30 [0.25–0.35]	0.29 [0.21–0.35]	0.38 [0.33–0.42]
PI-RADSv2 categories	T2w ⁽³⁾	0.50 [0.47–0.53]	0.59 [0.55–0.64]	0.53 [0.49–0.58]	0.43 [0.39–0.47]
	Dw ⁽³⁾	0.53 [0.49–0.56]	0.56 [0.53–0.60]	0.54 [0.50–0.58]	0.52 [0.48–0.56]
	DCE ⁽¹⁾	0.31 [0.26–0.35]	0.31 [0.26–0.36]	0.31 [0.22–0.37]	0.38 [0.33–0.43]
PI-RADSv2.1 score ⁽³⁾		0.42 [0.38–0.45]	0.47 [0.43–0.51]	0.43 [0.39–0.48]	0.39 [0.35–0.43]
PI-RADSv2 score ⁽³⁾		0.44 [0.40–0.47]	0.45 [0.41–0.49]	0.45 [0.41–0.49]	0.44 [0.40–0.49]

(1) Data are presented as mean kappa coefficient [95% confidence interval]
(2) Data are presented as mean concordance correlation coefficients [95% confidence interval]
(3) Data are presented as mean weighted kappa coefficients [95% confidence interval]
PZ Peripheral zone, TZ Transition zone, CZ Central zone, T2w T2-weighted, Dw Diffusion-weighted, PI-RADS Prostate imaging-reporting and data system