Quantifying neurobehavioral profiles across neurodevelopmental genetic syndromes and idiopathic neurodevelopmental disorders.

The study used caregiver-reported online questionnaires, mostly from parents, and did not include objective performance tests or multiple informants. NFIX and SYNGAP1 samples were small, and several rare syndromes were combined into one other neurodevelopmental genetic syndrome group, so syndrome-specific patterns may not generalise. Recruitment came through patient foundations and registries, which may create selection bias toward more impaired individuals or families already connected to these networks. Many group differences weakened after adjustment for age, estimated cognitive level, speech level and autism status, so some profiles may reflect general developmental impairment rather than a syndrome-specific effect. The sample had very high proportions of White participants and required English proficiency, which limits generalisability. Some quality of life and social motivation subscales had less adequate reliability or lower stability over 1 month and 4 months. Follow-up data were available for 422 participants at 1 month and 387 at 4 months, and a baseline power analysis used 374 participants excluding neurotypical controls. The study did not find significant changes over time or different changes over time between groups, so it did not establish clear longitudinal trajectories. The NET scales cover only the domains included in the questionnaire, so other important symptoms or skills may be missing.

Funding came partly from the PTEN Research Foundation, a charity, and from the Simons Foundation Autism Research Initiative, Autism Speaks, the SynGAP Research Fund, the Malan Syndrome Foundation and the ADNP Kids Foundation. Several authors reported financial relationships with these or related foundations, pharmaceutical companies or companies involved in autism or genetic syndrome assessment. An author, Tom Pepper, is employed by the PTEN Research Foundation, which partly funded the work. No other authors disclosed relevant conflicts.

Do not read these profiles as proof that a treatment will improve a named deficit. The study was observational, used caregiver report, and did not test any intervention; the NFIX and SYNGAP1 samples were small.