A moderado transtorno of intellectual development is a condition originating during the developmental period characterised by significantly below average intellectual functioning and adaptive behaviour that are approximately three to four standard deviations below the mean (approximately 0.003 – 0.1 percentile), based on appropriately normed, individually administered standardized tests or by comparable behavioural indicators when standardized testing is unavailable. Language and capacity for acquisition of academic skills of persons affected by a moderado transtorno of intellectual development vary but are generally limited to basic skills. Some may master basic self-care, domestic, and practical activities. Most affected persons require considerable and consistent support in order to achieve independent living and employment as adults.