SNAP-IV

SNAP-IV Assessment System for ADHD and ODD

The SNAP-IV, an acronym for "Swanson, Nolan, and Pelham, version IV," is a standardized and widely used rating scale designed specifically to assess the presence and severity of symptoms of Attention-Deficit/Hyperactivity Disorder (ADHD) and Oppositional Defiant Disorder (ODD) in children and adolescents, typically in the 6-18 age range.

Medical Specialty:
neurology

Patient Data

FOR PROFESSIONAL USE ONLY

This calculator is a support tool intended exclusively for health professionals. It does not replace clinical judgment. The final decision regarding diagnosis and treatment is the sole responsibility of the professional.

About this Calculator 💡

The SNAP-IV, an acronym for "Swanson, Nolan, and Pelham, version IV," is a standardized and widely used rating scale designed specifically to assess the presence and severity of symptoms of Attention-Deficit/Hyperactivity Disorder (ADHD) and Oppositional Defiant Disorder (ODD) in children and adolescents, typically in the 6-18 age range. This tool is not a test administered to the child, but rather a questionnaire completed by informants who observe the child in different settings, most commonly parents (or caregivers) and teachers. The scale is based directly on the diagnostic criteria from the DSM-IV (Diagnostic and Statistical Manual of Mental Disorders, 4th Edition). The most common version of the SNAP-IV is the 26-item scale, which is divided into three subscales: 9 items assessing symptoms of Inattention (ADHD-Inattentive criteria), 9 items assessing symptoms of Hyperactivity and Impulsivity (ADHD-Hyperactive/Impulsive criteria), and 8 items assessing symptoms of Oppositional Defiant Disorder. Each item describes a specific behavior (e.g., "Fidgets with hands or feet or squirms in seat"), and the informant (parent or teacher) rates the frequency of this behavior on a 4-point scale

Reference Values

  • •ADHD - Inattention
  • •0-17: Inattention symptoms below the clinical threshold
  • •18-27: Inattention symptoms suggestive of ADHD
  • •
  • •ADHD - Hyperactivity/Impulsivity
  • •0-17: Hyperactivity/impulsivity symptoms below the clinical threshold
  • •18-27: Hyperactivity/impulsivity symptoms suggestive of ADHD
  • •
  • •ODD - Oppositional Defiant Disorder
  • •0-11: ODD symptoms below the clinical threshold
  • •12-24: Symptoms suggestive of Oppositional Defiant Disorder

Formula

Calculation Methodology Sum the points for each domain separately. For ADHD: 6 or more symptoms with a score ≥2 in any domain. For ODD: 4 or more symptoms with a score ≥2.