Effectiveness of earlier antenatal screening for sickle cell disease and thalassaemia in primary care: cluster randomised trial.

OBJECTIVE: To evaluate the effectiveness of offering antenatal screening for sickle cell disease and thalassaemia in primary care as a way of facilitating earlier uptake of screening. DESIGN: Partial factorial cluster randomised controlled trial. SETTING: 25 UK general practices from deprived inner city areas. PARTICIPANTS: Anonymised data on all pregnant women attending participating practices during a six month period before randomisation and a seven month period after randomisation. This included 1708 eligible women. INTERVENTION: Practices were randomised to three groups for seven months: parallel testing in general practice (tests for sickle cell disease and thalassaemia offered to both parents when pregnancy was first reported); sequential testing in general practice (tests offered to mothers when pregnancy was first reported, and subsequently to the partners of women who were found to be carriers); and midwife care (tests offered to mothers at first consultation with a midwife). MAIN OUTCOME MEASURES: The primary outcome (available for all women) was the proportion of eligible women screened before 10 weeks' (70 days') gestation. Secondary outcomes were an offer of screening to women before 10 weeks' gestation, gestational age at testing, mean interval from first visit to the general practice visit to screening, and women's knowledge of the carrier status of their baby's father before 77 days' (11 weeks') gestation. The study was designed to detect a 20% absolute increase in screening uptake. Cluster level analyses were adjusted for age group, parity, ethnic group, primary care organisation, and number of general practitioners per practice. RESULTS: Data were analysed for 1708 eligible women. In the midwife care arm, 2% (9/441) of women were screened before 10 weeks' gestation compared with 24% (161/677) in the GP parallel testing arm and 28% (167/590) in the GP sequential testing arm. The estimated adjusted difference between the midwife care and GP parallel testing arms was 16.5% (95% confidence interval 7.1% to 25.8%; P=0.002) and between the midwife care and GP sequential testing arms was 27.8% (14.8% to 40.7%; P<0.001). By 26 weeks' gestation the proportion of women screened across the three trial arms was similar (81%). The proportion of women who knew the carrier status of the baby's father by 11 weeks' gestation was 0% (0/441) in the midwife care arm, 2% (13/677) in the GP parallel testing arm (P=0.003), and 1% (3/590) in the GP sequential testing arm (P=0.374). CONCLUSION: Offering antenatal screening for sickle cell disease and thalassaemia as part of consultations for pregnancy confirmation in primary care increases the proportion of women screened before 10 weeks' gestation. Even with intervention, however, only a minority of women were screened before 10 weeks. Additional interventions should be considered to achieve testing early in pregnancy for most women wanting such tests so that couples with affected pregnancies have less time pressure to choose options, which may include termination of the pregnancy. TRIAL REGISTRATION: Current Controlled Trials ISRCTN00677850.

Maximising recruitment and retention of general practices in clinical trials: a case study.

BACKGROUND: There is limited evidence regarding the factors that facilitate recruitment and retention of general practices in clinical trials. It is therefore pertinent to consider the factors that facilitate research in primary care. AIM: To formulate hypotheses about effective ways of recruiting and retaining practices to clinical trials, based on a case study. DESIGN OF STUDY: Case study of practice recruitment and retention to a trial of delivering antenatal sickle cell and thalassaemia screening. SETTING: Two UK primary care trusts with 123 practices, with a high incidence of sickle cell and thalassaemia, and high levels of social deprivation. METHOD: Practices were invited to take part in the trial using a research information sheet for practices. Invitations were sent to all practice managers, GPs, practice nurses, and nurse practitioners. Expenses of approximately pound 3000 per practice were available. Practices and the research team signed research activity agreements, detailing a payment schedule based on deliverables. Semi-structured interviews were completed with 20 GPs who participated in the trial. Outcome measures were the number of practices recruited to, and completing, the trial. RESULTS: Four practices did not agree to randomisation and were excluded. Of 119 eligible practices, 29 expressed an interest in participation. Two practices withdrew from the trial and 27 participated (two hosted pilot studies and 25 completed the trial), giving a retention rate of 93% (27/29). The 27 participating practices did not differ from non-participating practices in list size, number of GPs, social deprivation, or minority ethnic group composition of the practice population. CONCLUSION: Three factors appeared important in recruiting practices: research topic, invitation method, and interest in research. Three factors appeared important in retaining practices: good communication, easy data-collection methods, and payment upon meeting pre-agreed targets. The effectiveness of these factors at facilitating recruitment and retention requires assessment in experimental studies.

The reliability of "Analyze" software in measuring orbital volume utilizing CT-derived data.

INTRODUCTION: Craniomaxillofacial surgeons require to estimate the orbital volume in a variety of clinical situations. This paper evaluates a new method based on software analysis of computerized tomography (CT) scan data. MATERIAL AND METHODS: Five dried skulls with prosthetic globes and periorbita were non-helically scanned in an Elscint 2400 CT scanner. Images obtained were processed using the "Analyze" software package and results compared to the volume of the intraorbital prosthesis as determined by a volume displacement gravimetric method. RESULTS: Estimates of volume produced by the software varied from the gold standard by 0.06-50.44%, with a mean error of 8.8%. CONCLUSION: Despite the use of a variety of scan protocols it was not possible to obtain results with "Analyze" software which were sufficiently accurate for clinical use.