This paper compares the influence of the concept of the treating physician regarding guardianships requests diagnostic aids. Initially one considers the definition of attending physician, its concept and importance. Besides an analysis of the line of jurisprudence of the Constitutional Court on requests for diagnostic tests and referrals to specialists, according to the ruling of protection proffered by this institution between 2008 and 2013 is made. The research raised the following objectives: a) to relate guardianships and check which contradict or embrace the concept of the treating physician; b) analyzing that concept determined the judge’s ruling: application of the treating physician or EPS particular response of the Scientific Technical Committee or demand; and c) identify whether the judge ruled according to the fundamental right to conclude that the Constitutional Court has determined that the concept of the treating physician is binding and must be taken into consideration when defending the right.