Aims & Objectives: The Pediatric Index of Mortality (PIM) 2 and 3 have been used indistinctly. However, it is uncertain whether their results can be interpreted as clinically equivalent. We aim to determine the concordance for mortality risk classification obtained through the use of both scales. Methods: Through a retrospective cohort, we evaluated all patients admitted to the Pediatric Intensive Care Unit of a university hospital in Bogotá, Colombia, between April 2016 and December 2018 (n=722). We calculated mortality risk through PIM2 and PIM3 scores. Subsequently, an analysis was carried out to determine concordance between risk classifications obtained in both scales, using unweighted and linearly weighted kappa. Results: 722 subjects were included, 66.6% had a chronic condition. Global mortality was 3.7%. The global kappa concordance coefficient for classifying patients according to risk between the PIM 2 and the PIM 3 scores was moderate at 0.48 (95%CI 0.43-0.53). After linear weighting, concordance was substantial at 0.64 (95%CI 0.59-0.69). For the cardiac surgery patients, concordance for risk classification was fair at 0.30 (95%CI 0.21-0.39), even after linear weighting, concordance was only moderate at 0.49 (95%CI 0.39-0.59). PIM 3 assigned lower risk than PIM 2 in 44.8% of patients in this subgroup. Conclusions: Our study proves that PIM 2 and PIM 3 scales are not clinically equivalent and should not be used indistinctly for individual risk evaluation or for quality evaluation across pediatric intensive care units. Validation studies must be performed before using PIM 2 or PIM 3 in specific settings.