# Warning signs for identifying neurodevelopmental disorders: a systematic literature review

## TL;DR

This paper identifies common early warning signs for neurodevelopmental disorders in children, aiming to improve early detection and intervention.

## Contribution

A systematic review compiling the most consistent early red flags across multiple neurodevelopmental disorders for clinical use.

## Key findings

- Key early signs include motor delays, language delays, and social interaction deficits.
- Screening tools like M-CHAT-R/F and Bayley improve early detection accuracy.
- Early recognition combined with formal assessment is recommended for routine pediatric care.

## Abstract

To synthesize the most consistent warning signs (“red flags”) for NDDs: autism spectrum disorder, cerebral palsy, intellectual disability, language development disorder, coordination developmental disorder, attention deficit hyperactivity disorder, and global developmental delay.

Review in PubMed/Medline, Cochrane Library, SciELO, CAPES, and BVS, 2003-2025. Methodological quality was assessed with NOS, CASP, and AMSTAR.

54 studies were included. The most consistent early signs were grouped by NPMD domains: Motor: delay to sit ≥ 9 m, absence of independent walking 18 m, absence of pincer grasp 10 m, and asymmetrical motor patterns 12 m; Language: absence of babbling at 9–12 m, lack of words until 15–18 m, and absence of two-word combination 24 m; Social: absence of social smile, poor eye contact, deficits in shared attention and communicative gestures; Cognitive and behavioral: regression of skills, repetitive behaviors, absence of symbolic play, and irritability or inattention; Others: atypical sensory responses, sleep disturbances, and feeding difficulties. Instruments such as M-CHAT-R/F, ASQ, Bayley, and HINE increased the accuracy of screening and reduced referral delays.

Early recognition of warning signs for NPMD disorder associated with complementary examinations and formal assessment should be integrated into routine pediatric care.