Fig. 1

EHR-based Genomic Screening for CF. In a database of 50,778 participants, there were 50,754 negatives, namely cases without bi-allelic pathogenic CFTR variants, and 24 positives, namely cases with such variants. Amongst the negatives, eight had EHR data suggesting a CF diagnosis, six of those had no CFTR pathogenic variants, and two had a single pathogenic variant. Open chart review concluded that one of the heterozygotes was a false negative and one was a true negative. The remainder of the negatives, those without bi-allelic CFTR variants or EHR data consistent with CF were also considered true negatives. Open chart review was pursued for all 24 positive cases. The diagnosis of CF was confirmed in 21 cases. In the remaining three cases the diagnosis could not be confirmed due to insufficient available evidence