Development of a tool to measure the clinical response to biologic
therapy in uncontrolled severe asthma: the FEOS score.
Abstract
Background: There is a lack of tools to holistically quantify the
response to monoclonal antibodies (mAbs) in severe uncontrolled asthma
(SUA) patients. The aim of this study was to develop a valid score to
assist specialists in this clinical context. Methods: The score was
developed in 4 subsequent phases: (1) elaboration of the theoretical
model of the construct intended to be measured (response to mAbs); (2)
definition and selection of items and measurement instruments by Delphi
survey; (3) weight assignment of the selected items by multicriteria
decision analysis (MCDA) using the Potentially All Pairwise RanKings of
all possible Alternatives (PAPRIKA) methodology via the 1000Minds
software; and (4) face validity assessment of the obtained score.
Results: Four core items, with different levels of response for each of
them, were selected: “severe exacerbations”, “oral corticosteroid
use”, “symptoms” (evaluated by Asthma Control Test: ACT) and
“bronchial obstruction” (assessed by FEV1 % theoretical). “Severe
exacerbations” and “oral corticosteroid maintenance dose” were
weighted most heavily (38% each), followed by “symptoms” (13%) and
“FEV1” (11%). Higher scores in the weighted system indicate better
response and the range of responses runs from 0 (worsening) to 100 (best
possible response). Face validity was high (intraclass correlation
coefficient: 0.86). Conclusions: The FEOS score (FEV1, Exacerbations,
Oral corticosteroids, Symptoms) allows clinicians to quantify response
in SUA patients who are being treated with mAbs.