What is the Strengths and Weaknesses of Attention-Deficit/Hyperactivity Symptoms and Normal Behavior (SWAN) Questionnaire and how does it work?

The SWAN was developed by Swanson and colleagues (2015) to assess ADHD symptoms in clinical and non-clinical populations.

The SWAN includes a set of 18 questions that stem from the definition of ADD/ADHD outlined in the DSM-IV. A child’s behavior is scored on a 7-point scale ranging from far above average to far below average, with 4 (average) representing normal behavior for the child’s age.

This approach—comparing both positively and negatively to average children—helps minimize social-cultural and statistical biases. It also addresses the full range of strengths and weaknesses in attention-related behaviors, rather than only categorical classifications and pathological symptoms. Swanson’s team had previously created the SNAP-IV scale, but iterated on it to measure nuances in the severity of symptoms, resulting in the SWAN as an improved ADHD assessment tool.

Items 1 to 9 are associated with inattentive ADHD and items 10 to 18 are associated with hyperactive/impulsive ADHD. Scores are established by averaging scores in each subscale, then comparing the scores to research-based cutoff scores. Cutoff scores for each subtype were derived by averaging the results of multiple studies that determined cutoffs for optimal sensitivity and specificity for identifying patients with ADHD in clinical and community samples (Robaey et al., 2007; Chan et al., 2014; Alhaji, 2022). An average score above 0.745 on items 1-9 is indicative of inattentive ADD/ADHD, and (by coincidence) an average score above 0.745 on items 10-18 is indicative of the hyperactive/impulsive ADD/ADHD. Note that classifications are based on cutoff scores for parent ratings. Interpret reports based on teacher ratings with caution.

In studies establishing cutoff scores, the SWAN generally demonstrates high sensitivity for ADHD (82%+), but specificity varies depending on the study and population. False positive results (i.e., finding a score indicative of ADHD in a person who would not be diagnosed with ADHD by an expert) are possible, especially in clinical populations with comorbidities and diverse medical histories, or when ADHD is not necessarily suspected. Always follow up with objective cognitive testing, patient / guardian interviews, and most importantly, expert clinical judgment.