Purpose of the Study. To determine the specificity, sensitivity, and feasibility of using a 2-part (child + parent questionnaire) case finding tool (Video-guided Asthma Screening for Children-School Age, VASC-SA) to identify elementary school children with asthma.
Study Population. A total of 350 matched parent-child pairs
Methods. As part of the VASC-SA, children and parents were both queried. The child checklist included 2 practice items and 9 items asking about asthma symptoms and diagnosis. The items were visually cued using a 10-minute videotape using split-screen vignettes, one corresponding to a no response (most children do not …) and one to a yes response (some children …). Three case definition algorithms were examined (all included inhaled medication, or current diagnosis, or wheeze with 0, 1, or 2 other symptoms). The VASC-SA was administered to English-speaking children in grades 1 to 4 from one school. All parents were sent a written asthma questionnaire. Positive screens were compared with diagnosis obtained from physician report or parent interview.
Results. Asthma prevalence in this sample ranged from 14% to 14.9% using VASC-SA case definitions. Sensitivity for the 3 definitions ranged from 79% to 81% and specificity ranged from 94.5% to 95%. The predictive value positive ranged from 66% to 69% and predictive value negative was 97%. Concordance of child and parent reports was highest for previous asthma diagnosis and use of inhaled medication.
Conclusions. The VASC-SA appears to be a promising new epidemiologic tool to facilitate asthma screening in elementary schools. Prescreening children before parents may offer a practical approach in a large, community-based population.
Reviewer’s Comments. The authors observed that even more restrictive definitions of asthma eg, wheeze plus 1 or 2 other symptoms, or medications, or current diagnosis did not significantly alter the sensitivity or specificity of results (beyond simply wheezing alone, or medications, or current diagnosis). They also point out that the sensitivity and specificity of child-reported symptoms alone were low and thus inadequate without parental verification. Surprisingly, 30% of children with a parent diagnosis of asthma were unknown to the school nurse before the study. In addition, eight children (2.2%) received a new diagnosis of asthma as a result of the screening. Future longitudinal studies should include assessment of asthma severity and follow-up for those with a positive screen (to get a sense of the clinical impact of using the VASC-SA).
- Copyright © 2002 by the American Academy of Pediatrics