Interpreting the Hospital Anxiety and Depression Scale (HADS) for Individuals with Traumatic Brain Injury: Clinical Correlates and Empirical Severity Cut-Offs

Anxiety and depression symptoms are more prevalent in individuals with moderate-severe traumatic brain injury (TBI) than the general population, underscoring the need for effective screening. The Hospital Anxiety and Depression Scale (HADS) is widely used for this purpose, yet, how best to use and interpret the HADS in individuals with TBI remains an open question. This study evaluated the HADS total score, subscale scores, and individual items in 402 individuals with moderate-severe TBI. The sample was on average 13 years post-injury, originally recruited during inpatient rehabilitation. HADS scores were regressed against five clinically important variables to determine their concurrent criterion validity, and regression tree analyses were used to establish severity cut-offs on the total and subscale scores. Results indicated that while the HADS subscale scores provided no meaningful advantage over the total score in terms of accounting for variance in suicidal ideation, self-harm, or mental health treatment, the subscales—particularly depression-related items—were more informative regarding functional disability and life satisfaction. Benchmarked against these clinically important variables, we established graded severity cut-offs (‘normal’, ‘mild’, ‘moderate’, and ‘severe’) for both the HADS total and subscale scores. This study provides clinicians and researchers with empirically-derived guidance for using and interpreting the HADS when assessing emotional distress in individuals with moderate-severe TBI. Keywords: moderate-severe TBI, clinically important variables, levels of abstraction