Nowadays, in some Spanish autonomous communities, between 30% to 50% of the Primary CarePediatric positions are carried out by professionals without specific training in the specialty.In addition, when Spanish general practitioners with pediatric practice complete their Resident Medical Intern program are not evaluated on their Pediatric Cardiology clinical reasoning. Actual unawareness about this knowledge precludes professional retraining directed to solve deficiencies in this collective.Script Concordance Test is a new clinical reasoning assessment tool which places examinees in real clinical situations in which they have to interpret data and assess hypothesis to make decisions. This tool allows getting consistent data through variables analysis but it still hasn't been used in Spain for health professional's evaluation so far.Our goal is the development, validation, and application of a Script Concordance Test for clinical reasoning analysis in Pediatric Cardiology to ensure if practitioners attending children have enough Pediatric Cardiology knowledge for safe practice and to learn if qualification, Pediatric Cardiology formation, years of pediatric practice, and training course completion influence the score obtained.Our method describes a Script Concordance Test which was approved by a Pediatric Cardiology experts committee, met reliability criteria, allowed distinguishing evaluated subject different formative grade (188 pediatricians and 38 general practitioners), and was accessible for investigators. A statistical study including demographic and employment variables and achieved scores was performed to study a possible relationship between them.4 pediatricians (2.1%) and 1 GP (2.6%) didn't pass the questionnaire. Pediatric Cardiology qualification and training programs influenced more in Pediatric Cardiology clinical reasoning than the accumulation of years of pediatric practice and the frequency of this practice. We observed that the older the professional was, the lowest the score in the questionnaire.