i need help - algebra metaphor

this was my first try. beth thought it had promise but rebecca laughed at the simplicity and struck it down with an iron fist of fury....

The medical model treats patients like algebraic equations. Doctors take a diagnosis, apply the prescribed treatment, and then watch for an improved outcome—if x is diabetes, make y insulin; for syphilis, administer penicillin. But in contemporary psychiatry, mental health practitioners must contend with a frustrating disconnect between diagnosis and treatment. Indeed, patients are sometimes more responsive to a physician’s last-chance pharmaceutical blend than any regiment that is particular to the patients’ diagnoses.