RT Journal Article
SR Electronic
T1 The construction and validation of the Severe Asthma Questionnaire
JF European Respiratory Journal
JO Eur Respir J
FD European Respiratory Society
SP 1800618
DO 10.1183/13993003.00618-2018
VO 52
IS 1
A1 Michael E. Hyland
A1 Rupert C. Jones
A1 Joseph W. Lanario
A1 Matthew Masoli
YR 2018
UL http://erj.ersjournals.com/content/52/1/1800618.abstract
AB The US Food and Drug Administration's procedure for scale validation requires a documented stepwise process of qualitative and quantitative data. The aim of this paper is to provide final quantitative validating data for the Severe Asthma Questionnaire (SAQ).The SAQ, Asthma Control Test, Mini Asthma Quality of Life Questionnaire and EQ-5D-5L were completed by 160 patients attending a severe asthma clinic; 51 patients completed the SAQ on two occasions for test–retest reliability analysis. The SAQ produces two scores, a SAQ score based on the average of 16 items and a SAQ-global score from a single 100-point global quality of life scale.Construct validity was demonstrated by factor analysis of the 16 items, convergent validity by correlations of >0.6 between the SAQ, SAQ-global and other questionnaires, and discriminant validity by the ability of the SAQ and SAQ-global to distinguish between different treatment levels. Test–retest reliability (intra-class correlation) was 0.93 for the SAQ and 0.93 for the SAQ-global, and the alpha coefficient for the SAQ was 0.93.The SAQ was developed using recommended qualitative and quantitative procedures for scale development, and can be used to gain insight into patients’ perceptions of how severe asthma and its treatment affects their lives.Validating a new severe asthma-specific quality of life questionnaire, the SAQ http://ow.ly/sSNW30k3Pbu