Should we screen all newborns for cystic fibrosis?.

To assess the value of detecting albumin in meconium as a screening 
procedure for cystic fibrosis [CF] 68,000 meconium samples were examined by 
BM Meconium Test, single radial immunodiffusion and benzidine reaction. The specificity 
and sensitivity of this combination of tests were 99.67% and 78.57% 
respectively. The prevalence of CF at birth was confirmed as 1:3600 
in this country. This low prevalence resulted in a relatively high 
number of false positives. Therefore, a positive test result has a 
low predictive value [3.39%] and this is a serious drawback of 
the method. The experiences and opinions of 37 local paediatricians about 
the screening programme were evaluated by a simple questionnaire. Gold's decision 
rule was applied. The least relative cost of misclassification justifying a 
mass-screening programme was 3 times higher than the actual relative cost 
as suggested by the aggregate opinion of paediatricians in the region. 
These results support the view that with the methods used screening 
may have more disadvantages than not screening. 