Probability of Detection models, for a specific NDE system, is very important to assess the probability at which a flaw of certain dimension can be detected. This paper proposes a fully model assisted probability of detection (MAPOD) with a Bayesian decision to classify the flaw size. Multiple correlated flaw features were integrated to the POD analysis. This was made by assigning the observation model directly to a multivariate Gaussian distribution. The mean and covariance of the distributions were empirically computed to form a Gaussian Mixture Model (GMM) to obtain the classical Hit/Miss POD curve. A risk analysis was performed on the probability of misclassification considering a 0/1 loss function. Classification decisions were made from the posterior estimates within the Bayesian framework. For the analysis, a finite element simulation study was performed for a flaw located at the sub-surface of a stainless steel (SS304) specimen.