Development and validation of asthma diagnostic scale for Chinese children under 6 years old

Background: There is no diagnostic criteria for asthma in children under 6 years of age up to now. Objective: To construct an asthma diagnostic scale for children (< 6 years old) to improve the diagnosis of asthma in China. Methods: : Electronic medical record database of a hospital was used to develop the scale. Item pool was established through literature survey and expert opinion, the screening and optimization of items were conducted by using Delphi method, t-test, reactivity analysis, Pearson correlation coefficient, factor analysis, reliability and validity test. The predictive probability of asthma was calculated using the logistic regression, and the receiver operating characteristic (ROC) curve evaluated the diagnostic efficiency of the scale. Another childhood asthma database validated the scale. Results: : The asthma diagnostic scale for children (< 6 years old) included five dimensions: dimension 1 (shortness of breath, three concave sign, cyanosis, moist rale, heart rhythm, heart sound and dyspnea), dimension 2 (respiratory sound, cough, sputum), dimension 3 (frequency of wheezing, allergic rhinitis, history of allergy in one or both parents), dimension 4 (gender, wheezing sound, atopic dermatitis), and dimension 5 (reversible airflow, positive in vitro or in vivo allergy test). Cronbach’s α coefficients for the five dimensions were 0.846, 0.459, 0.019, 0.202, and 0.024. The area under the ROC curve (AUC), sensitivity, and specificity were 0.737, 59.1%, and 81.2%. AUC, sensitivity, and specificity of the validation data were 0.614, 76.2%, and 46.7%. Conclusion: The asthma diagnostic scale for children (< 6 years old) had certain reliability, validity, and diagnostic efficiency.