Validation of the Hospital Asthma Severity Score (HASS) in children ages 2-18 years old

Introduction: The Hospital Asthma Severity Score (HASS) was developed to communicate inpatient asthma severity between providers. The purpose of this prospective study was to validate the HASS against the Pediatric Respiratory Assessment Measure (PRAM) and spirometry for assessment of inpatient asthma exacerbation severity in patients 2-18 years old, at a single point-in-time.

Methods: This study was registered with clinicaltrials.gov (NCT02782065). Children admitted to a tertiary care, free-standing children's hospital were assessed for asthma severity using the HASS, PRAM, and pulmonary function by spirometry. Inter-rater agreement of HASS and PRAM scores was assessed between two blinded clinician raters. Spirometry results were obtained by a certified pulmonary laboratory technician and correlated with HASS and PRAM scores.

Results: The sample included 58 subjects. Allowing for a one-point difference in continuous HASS and PRAM scores, inter-rater agreement was 79% for the HASS and 60% for the PRAM. When the scores were categorized as mild, moderate, and severe, inter-rater agreement was 62% for the HASS and 93% for the PRAM (p < .0001). Additionally, intra-rater agreement between HASS and PRAM severity categories was 71% for Rater 1 and 64% for Rater 2. A weak correlation was noted between both the HASS and FEV₁ (r = -0.31; p = 0.11), and PRAM and FEV₁ (r = -0.30; p = 0.11) for the 29 subjects with acceptable spirometry results.

Conclusions: The HASS and PRAM have acceptable inter-rater and intra-rater agreement. These results support validation of the HASS for managing hospitalized patients during asthma exacerbations.