Evidence suggests that previous uses of willingness to pay (WTP) to value close substitutes may have failed to discriminate between the alternatives being evaluated. This paper reports on the application of a new technique for measuring WTP in such contexts. The alternatives evaluated are two methods of screening for cystic fibrosis carrier status. The results suggest that the new method is more discriminating. Furthermore, the paper provides evidence, from reasons for respondents' WTP valuations and regression analyses, that the use of open-ended WTP questions is not valid. This is in line with the recommendations of a recent, influential, report on the use WTP techniques.

Analysis of Variance↗

PubMedDate not supplied

Willingness to pay for antenatal carrier screening for cystic fibrosis.

We report on a study of women's willingness to pay (WTP) for a cystic fibrosis carrier test by one or other method of service delivery (disclosure or non-disclosure). The results demonstrate that there was no statistically significant difference in WTP for the methods of testing. Those women who received a negative test result were followed up and asked their WTP for such a result. Values obtained at this stage were 16 per cent higher than those obtained pretest result. Use of prompts, rather than simply asking women to state their WTP, had a statistically significant effect on post-test result values. The opportunity to terminate the pregnancy, if a test proved positive, was important, but was not the only consideration. This demonstrates the importance to women of other benefits of screening.

Abortion, Eugenic↗

PubMedDate not supplied

A comparative study of two devices used for cervical cell sampling raises some doubts about liquid-based cytology.

The objective of this study was to compare the quality of smears obtained by a newly designed cervical cell sampler (the implement) to those obtained with the cervex brush, using liquid-based cytology (LBC). A prospective randomized controlled trial with the approval of the local ethics committees after informing the Medical Devices Agency in the UK was used in this study. The study was carried out in colposcopy clinics in two district general NHS Trust Hospitals in London. A total of 200 women were recruited (100 from each hospital). The women were randomized into two groups, each of them having two smears at the same time. One hundred (50%) of the women had their first smear with the new implement, and the other 100 (50%) had their first smear with the cervex brush. The main outcome of this study is good-quality smears, assessed by evidence of effective sampling of the transformation zone, including immature metaplastic cells and also endocervical cells. Eighty-five percent of the smears taken by the new implement showed good-quality smears compared to 91% of those taken by the cervex brush, a statistically marginally nonsignificant result, with P value = 0.052 (McNemar exact test). A larger number of good-quality smears, judged by evidence of sampling of transformation zone, were obtained with the cervex brush, though the difference was statistically marginally nonsignificant, using the British society for clinical cytology criteria. Surprisingly, despite the use of LBC, there was a higher rate of inadequate smears obtained with both the devices (8% with each) compared to our previous study using the conventional slide test (1.3% with the new implement and 1.8% with the Jordan's spatula).

Cytodiagnosis↗

PubMedDate not supplied

Hyperacute infarction: early CT findings.

The aim of our study is to determine how early and reliably ischemic brain infarcts can be detected on CT scanning. We report two cases of an early CT finding of acute ischemic infarcts where CT examination was obtained within the first 3 hours of onset of neurological symptoms. CT examination showed blurred outlines and decreased attenuation of the left lentiform nucleus, loss of the white-gray matter interface in the left insular cortex and left cortical global hypoattenuation with obliteration of left cortical sulci in one patient. In second patient CT showed the following: hyperdense left middle cerebral artery, loss of clear margins of left lentiform nucleus, subtle focal cortical hypodensity in the left fronto-parietal area with signs of mass effect in the form of ventricular compression. CT is still the first choice in the deferential diagnosis of acute stroke. Although older literature positions have suggested that CT was negative during the first 48 hours, modern CT technology can demonstrate positive findings even in the first 3 hours of onset. This is important in patients with acute stroke, as thrombolytic therapy when elected, has to be given within the first 3-6 hours after onset of symptoms. To determine how early and reliably ischemic brain infarcts can be detected on CT scanning, we report two cases of an early CT finding of acute ischemic infarcts where CT examination was obtained within the first 3 hours of onset of neurological symptoms.

Acute Disease↗