I want to determine the fuzzy intervals in a medical fuzzy system but physicians who consult to me do not have any view about fuzzy decisions . They say me "according our medical references , anything is crisp and based on discrete values" . I disappointed from their helps and now want to determine this fuzzy MFs based on clinical guidelines and aome experiences in medicine. Is there a machine learning or wizard or default and simple and basic method to determine these parameters ? I want a scientific approach if exists ?!