<b><i>Background:</i></b> Over the last decades, the use of gastrointestinal (GI) endoscopic procedures has been increased in children worldwide, allowing the early diagnosis and therapeutic intervention in multiple GI diseases. <b><i>Aims and Methods:</i></b> In order to evaluate the appropriateness and the diagnostic yield of initial GI endoscopic techniques in children in a Portuguese tertiary hospital, we performed a retrospective cohort study during a 12-month period.<b><i> Results:</i></b>A total of 308 procedures were performed in 276 patients; the median age was 11 years and 50.4% were males. Esophago-gastro-duodenoscopy (EGD) corresponded to 81.8% of the procedures and ileo-colonoscopy (IC) to the remaining; 11.6% of the patients underwent both EGD and IC. Overall, 51.3% of the exams showed abnormal macroscopic findings, and 69.6% showed histopathological signs of disease, with IC showing significantly more positive results than EGD (<i>p</i> < 0.05). Considering the different indications independently, abnormal serology for celiac disease, suspected ingestion of foreign bodies, suspected inflammatory bowel disease, and food impaction were frequent in our population; and in the majority of the cases, the suspected diagnosis was confirmed: celiac disease, ingestion of foreign bodies, inflammatory bowel disease, and eosinophilic esophagitis, respectively. On the other hand, despite the high frequency of epigastric pain in this population, only nearly one-third of the patients showed abnormal histological findings. The final diagnosis was established in 63% of the patients, and 39.1% initiated the new treatment.<b><i> Discussion:</i></b>Our results emphasize the importance of endoscopic procedures, especially IC, in the diagnosis of GI diseases in pediatric patients, as well as the careful choice of the endoscopic techniques in those with less specific symptoms, as chronic abdominal pain. In this particular situation, given the proportion of cases that may be due to functional disease, good characterization of the clinical context is needed, and endoscopy should be reserved for a second-line approach. <b><i>Conclusion:</i></b> It is important to monitor and examine the endoscopic techniques as an index of quality criteria for clinical practice.
