NBD can take many forms: difficulties with social cognition, such as problems recognising or expressing emotion; poor inhibitory control, including impulsivity, irritability, mood lability, and temper loss; or a marked reduction in motivation, drive, and engagement with others.

These changes are associated with poor rehabilitation outcomes, reduced quality of life, social handicap, and an increased risk of contact with the criminal justice system. Therefore, having reliable tools to assess NBD is essential to support timely intervention and guide effective care.

Assessment plays a crucial role in guiding clinical decision-making and treatment planning throughout the course of rehabilitation. It also enables services to evaluate the effectiveness of interventions — a vital component in demonstrating both clinical impact and cost-effectiveness.

The St Andrew’s–Swansea Neurobehavioural Outcome Scale (SASNOS) was developed to fill this critical gap. Specifically designed for ABI, SASNOS provides a robust, purpose-built assessment tool capable of measuring the unique characteristics of NBD with reliability, validity, and responsiveness.

Grounded in the WHO-ICF framework and developed through rigorous psychometric methods, SASNOS is a 49-item tool that captures five key domains of NBD: Interpersonal Relationships, Cognition, Inhibition, Aggression, and Communication.

Since 2011, SASNOS has been adopted by major neurorehabilitation providers, embedded in electronic health records, endorsed by professional/medical organisations, translated into multiple languages, and used in over 18 countries worldwide.