Simple multivariable scores for asthma screening
Published online: July 18, 2018
Asthma is an important public health problem that affects people of all ages and causes significant personal and social burden. The asthma estimates obtained in surveys are highly dependent on the set of questions used to define asthma. The identification of asthma in adults is still an issue, and a screening questionnaire to rule-in and rule-out asthma is lacking.
In a study published in The Journal of Allergy and Clinical Immunology: In Practice, Sá-Sousa and colleagues developed and validated scores for adult asthma identification in epidemiological studies and clinical screening/triage settings. A set of self-administered questions from a literature review (A2-score) and from the Global Allergy and Asthma Network of Excellence (GA2LEN) questionnaire (GA2LEN-score) were answered by 711 adults from a nationwide population-based study. Respondents were randomly allocated to the derivation (n=560) and validation (n=151) cohorts. The scores and the cut-offs to rule-in and rule-out asthma were explored and further validated and compared with the physician diagnosis of asthma.
The authors developed and validated two short, easy to use scores, consisting of a simple sum of positive answers. The A2-score comprises 8 questions (including “Did a physician confirm you had asthma?”) and GA2LEN-score with 6 questions (including “Have you ever had asthma?”). Asthma presence (rule-in) can be considered for ≥4 positive answers in either A2-score or GA2LEN-score. Asthma can be excluded (rule-out) for results of 0 in GA2LEN-score or of 0 to 1 in A2-score. For results in between, asthma is possible but requires a confirmatory clinical evaluation. These scores presented very good predictive properties providing validated screening tools. The A2-score may be preferred in studies aiming at maximum accuracy; however, the GA2LEN-score is shorter and would be preferable for communities where there may be difficulties related to physician diagnosis of asthma.
These practical, easy to use scores allow healthcare professionals and researchers to screen for asthma and identify it with a high level of discrimination as well as select the best candidates to be referred for diagnostic workup. Moreover, by helping to reduce the inconsistencies of operational definitions of asthma across epidemiological studies and surveys, these scores allow for homogenization and better reliability of asthma estimates.
The Journal of Allergy and Clinical Immunology: In Practice is an official journal of the AAAAI, focusing on practical information for the practicing clinician.
Adult asthma scores - development and validation of multivariable scores to identify asthma in surveys
By Ana Sá-Sousa, Ana Margarida Pereira, Rute Almeida, Luís Araújo, Mariana Couto, Tiago Jacinto, et al