Lessons for intermediate and low prevalence areas in England from the Ethnicity Questions and Antenatal Screening for sickle cell / thalassaemia [EQUANS] study

Date
2007
Authors
Dyson, Simon
Chambers, Keith
Gawler, Sue
Hubbard, Stephanie
Jivanji, Vanita
Sutton, Faye
Squire, Patricia
Journal Title
Journal ISSN
ISSN
1743-1913
DOI
Volume Title
Publisher
Radcliffe
Peer reviewed
Abstract
This study evaluates a temporary research-based intervention of universal ante-natal screening for sickle cell/thalassaemia in two areas of England of intermediate (1.29 per 10,000) and low (0.18 per 10,0000) expected foetal prevalence for sickle cell disease (SCD). It also assesses the comprehensiveness of coverage in levels of laboratory tests requested of risk groups for SCD identified by an ethnicity screening question. The design was a ten month (Sept 2002-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. 2,922 pregnant women were recruited at their first booking with midwife (of 3,255 recorded as invited, from a possible 12,424 women recorded as booking). 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 ante-natal 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% CI: 0.01% to 0.71%, p= 0.045). In the low prevalence 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 haemoglobinopathy screen. In a low prevalence area, use of evidence-based ethnicity screening questions increases the proportion of clients identified as at risk of carrying genes associated with sickle cell or thalassaemia. In order to minimise the rates of failing to offer laboratory screening in a low prevalence area, midwives require specific training on the screening process, and which risk groups to offer a laboratory screen.
Description
Keywords
sickle cell, thalassaemia, screening, ante-natal, ethnicity, health policy, low prevalence, haemoglobinopathies, England
Citation
Dyson, S. et al. (2007) Lessons for intermediate and low prevalence areas in England from the Ethnicity Questions and Antenatal Screening for sickle cell / thalassaemia [EQUANS] study. Diversity in health and social care, 4 (2), pp. 123-35.
Research Institute
Institute for Allied Health Sciences Research