Validation of the Asthma Severity Scoring System (ASSESS) in the ALLIANCE cohort.

BACKGROUND

The Asthma Severity Scoring System (ASSESS) quantifies asthma severity in adolescents and adults. Scale performance in children < 12 years is unknown.

OBJECTIVE

To validate the ASSESS score in the All Age Asthma Cohort (ALLIANCE) and explore its use in children <12 years.

METHODS

Scale properties, responsiveness, and known-group validity were assessed in 247 children (median age 11 years, IQR: 8-13 years) and 206 adults (median age 52 years, IQR: 43-63 years).

RESULTS

Overall, measures of internal test consistency and test-retest reliability were similar to the original data of the Severe Asthma Research Program (SARP). Cronbach's α was 0.59 in children 12-18 years and 0.73 in adults, reflecting the inclusion of multiple and not always congruent dimensions to the ASSESS score especially in children. Analysis of known-group validity confirmed the discriminatory power, as the ASSESS score was significantly worse in patients with poor asthma control, exacerbations and increased salbutamol use. In children between 6-11 years test reliability was inferior compared to adults and adolescents (Cronbach's α 0.27) mostly due to a less lung function impairment in asthmatic children of this age group. Known-group validity however confirmed good discriminative power regarding severity-associated variables similar to adolescents and adults.

CONCLUSION

Test reliability and validity of the ASSESS score was confirmed in the ALLIANCE cohort. In children aged 6-11 years internal consistency was inferior compared to older asthma patients, however test validity was good and encourages age-spanning usage of the ASSESS score in all asthma patients ≥ 6 years.