Simon M Dyson, Keith Chambers, Sue Gawler, Stephanie Hubbard, Vanita Jivanji, Faye Sutton, Patricia Squire
This study evaluated a temporary research-based intervention of universal antenatal screening for sickle cell/thalassaemia in two areas of England: one of intermediate (1.29per 10 000) and the other of low (0.18 per 10 000) expected fetal prevalence for sickle cell disease (SCD). The study also assessed the comprehensiveness of coverage in levels of laboratory tests requested for risk groups for SCD identified by an ethnicity-screening question. The design was a 10-month (September 2002 to June 2003) questionnaire study with random allocation to two ethnicity-screening questions and comparison with: (1) laboratory results; (2) numbers of laboratory screens requested; (3) numbers of laboratory screens undertaken; (4) an equivalent period before intervention; and (5) ethnic-monitoring data. Altogether 2922 pregnant women were recruited at their first booking with a midwife (of 3255 recorded as invited, from a possible 12 424 women recorded as booking). Outcomes showed that, in a move from a selective screening programme to a temporary, research-based universal screening programme, the intermediate-prevalence area increased screening coverage from 20.7% to 42.6% of the antenatal population. Carriers of sickle cell, thalassaemia and other haemoglobinopathies identified during the study period increased from 86 to 118, representing a proportional increase of 0.36% (95% confidence interval 0.01% to 0.71%, P = 0.045). In the lowprevalence area,with a selective screening programme, the proportion identified as at risk using specifically designed ethnicity-screening questions, as opposed to generic ethnic monitoring using locally devised categories, increased from 2.2% to 13.0% (P 0.001). Only 10% of those identified as at risk by the ethnicity-screening questions were offered a laboratory
