1. A method for processing sensor data representative of a body, comprising the steps of: using a physical model, representative of function of a body constituent, coded into a digital signal processor of an analyzer, wherein said physical model comprises the step of: using a fitting constant related to at least one of age and gender; generating a prior probability distribution function using said physical model; repetitively fusing input data originating from at least a first medical instrument and a second medical instrument with the prior probability distribution function to generate a posterior probability distribution function; and processing the posterior probability distribution function with said processor to generate an output of least one of: a heart attack prediction; and a heart stroke volume, wherein said step of processing uses at least one equation relating heart stroke volume to the posterior probability distribution function.