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Objectives: To evaluate diagnostic performance of different mathematical models and different b-values of diffusion weig htedimaging in peripheral zone prostate cancer detection.Methods: 56 patients with peripheral PCa underwent DW-M RI by using 21 b-values (0-4500s/m m2) at 3.OT. The mean signalintensities of ROIs placed in normal peripheral tissue and peripheral PCa were fitted using the four models (conventional mono-exponential, bi-exponential, stretched-exponential, and ku rtosis). To validate the dependence of modes on the b-values, the b-values were divided into four different ranges: 0-1000, 0-2000, 0-3200, and 0-4500 s/m m2, titled as groups A, B, C, and D,respectively. ADC, D, D*, f, DDC, a, Dapp, Kapp were estimated for every g rou p. In order to test goodness-of-fit, adjustedcoefficient of determinant (R2) for g roups were calculated among diffe rent models. Receiver operating cha ra cteristic cu rve (ROC)analysis was performed and the area under the cu rve (AUC) was obtained to evaluate and compa re the diagnostic accu racy ofpa ra meters in distinguishing cancerous tissues from normal PZ.Results: The bi-exponential and the stretched-exponential models provide the hig hest adjusted R2 among the four models inevery g rou p. The ku rtosis model provide the medium goodness-of-fit. The mono-exponential model provide the lowestgoodness-of-fit in the four g roups. All para meters except D* show sig nificant diffe rent between ca ncerous tissues and normal PZin each g roup. Whether in the PCa or in benign PZ, the mean value of all parameters except DDC are varietied with thedecreasing of the b value. The AUCs of ADC, D, DDC and Kapp calculated using the optimal b-value ra nge were the highestamong four model. AUCs of ADC and Kapp a re compara ble in four groups, and sig nificantly higher than other pa ra meters. TheAUC of ADC was comparable in group C and D (p > 0.05) and higher with respect to group A and B (all p<0.05).Conclusions: ADC derived from conventional mono-exponential high b-value (3000s/m m2 ) remains optional for clinical routineapplication in peripheral zone PCa detection. DDC derived from stretched-exponential is an alternatively promising parameter toADC for its good diagnostic performance and sta bility though the b-value adopted.