London School of Economics and Political Science

About: London School of Economics and Political Science is a education organization based out in London, United Kingdom. It is known for research contribution in the topics: Politics & Population. The organization has 8759 authors who have published 35017 publications receiving 1436302 citations.

Sensitivity and specificity of multimodal and ultrasound screening for ovarian cancer, and stage distribution of detected cancers: Results of the prevalence screen of the UK Collaborative Trial of Ovarian Cancer Screening (UKCTOCS)

Abstract: Background: Ovarian cancer has a high case–fatality ratio, with most women not diagnosed until the disease is in its advanced stages. The United Kingdom Collaborative Trial of Ovarian Cancer Screening (UKCTOCS) is a randomised controlled trial designed to assess the effect of screening on mortality. This report summarises the outcome of the prevalence (initial) screen in UKCTOCS. Methods: Between 2001 and 2005, a total of 202 638 post-menopausal women aged 50–74 years were randomly assigned to no treatment (control; n=101 359); annual CA125 screening (interpreted using a risk of ovarian cancer algorithm) with transvaginal ultrasound scan as a second-line test (multimodal screening [MMS]; n=50 640); or annual screening with transvaginal ultrasound (USS; n=50 639) alone in a 2:1:1 ratio using a computer-generated random number algorithm. All women provided a blood sample at recruitment. Women randomised to the MMS group had their blood tested for CA125 and those randomised to the USS group were sent an appointment to attend for a transvaginal scan. Women with abnormal screens had repeat tests. Women with persistent abnormality on repeat screens underwent clinical evaluation and, where appropriate, surgery. This trial is registered as ISRCTN22488978 and with ClinicalTrials.gov, number NCT00058032. Findings: In the prevalence screen, 50 078 (98·9%) women underwent MMS, and 48 230 (95·2%) underwent USS. The main reasons for withdrawal were death (two MMS, 28 USS), non-ovarian cancer or other disease (none MMS, 66 USS), removal of ovaries (five MMS, 29 USS), relocation (none MMS, 39 USS), failure to attend three appointments for the screen (72 MMS, 757 USS), and participant changing their mind (483 MMS, 1490 USS). Overall, 4355 of 50 078 (8.7%) women in the MMS group and 5779 of 48 230 (12·0%) women in the USS group required a repeat test, and 167 (0·3%) women in the MMS group and 1894 (3·9%) women in the USS group required clinical evaluation. 97 of 50 078 (0·2%) women from the MMS group and 845 of 48 230 (1·8%) from the USS group underwent surgery. 42 (MMS) and 45 (USS) primary ovarian and tubal cancers were detected, including 28 borderline tumours (eight MMS, 20 USS). 28 (16 MMS, 12 USS) of 58 (48·3%; 95% CI 35·0–61·8) of the invasive cancers were stage I/II, with no difference (p=0·396) in stage distribution between the groups. A further 13 (five MMS, eight USS) women developed primary ovarian cancer during the year after the screen. The sensitivity, specificity, and positive-predictive values for all primary ovarian and tubal cancers were 89·4%, 99·8%, and 43·3% for MMS, and 84·9%, 98·2%, and 5·3% for USS, respectively. For primary invasive epithelial ovarian and tubal cancers, the sensitivity, specificity, and positive-predictive values were 89·5%, 99·8%, and 35·1% for MMS, and 75·0%, 98·2%, and 2·8% for USS, respectively. There was a significant difference in specificity (p<0·0001) but not sensitivity between the two screening groups for both primary ovarian and tubal cancers as well as primary epithelial invasive ovarian and tubal cancers. Interpretation: The sensitivity of the MMS and USS screening strategies is encouraging. Specificity was higher in the MMS than in the USS group, resulting in lower rates of repeat testing and surgery. This in part reflects the high prevalence of benign adnexal abnormalities and the more frequent detection of borderline tumours in the USS group. The prevalence screen has established that the screening strategies are feasible. The results of ongoing screening are awaited so that the effect of screening on mortality can be determined. Funding: Medical Research Council, Cancer Research UK and the Department of Health, UK; with additional support from the Eve Appeal, Special Trustees of Bart's and the London, and Special Trustees of University College London Hospital.

Effects of Privatization and Ownership in Transition Economies

Abstract: The paper evaluates the effects of privatization in the post-communist economies and China. In post-communist economies privatization to foreign owners results in a rapid improvement in performance of firms, while performance effects of privatization to domestic owners are less impressive and vary across regions, coinciding with differences in policies and institutional development. In China relatively more estimates suggest that privatization to domestic owners improves the level of performance. Concentrated private ownership has a stronger positive effect on performance than dispersed ownership in the post-communist economies, but foreign joint ventures rather than wholly owned foreign firms have a positive effect in China. Worker or collective ownership does not have a negative effect. In the post-communist economies new firms are equally or more efficient than firms privatized to domestic owners, and foreign start-ups are more efficient than domestic ones. Privatization is not associated with lower employment. When accompanied by complementary reforms, privatization has a positive effect on economic growth. Three factors appear to drive the more positive effect of privatization to foreign than domestic owners. Domestic managers have more limited skills and access to world markets, domestically privatized firms have been more subject to tunneling and in some countries new large shareholders artificially decreased performance. The important policy implication is that privatization per se does not guarantee improved performance, at least not in the short- to medium-run. Type of private ownership, corporate governance, access to know-how and markets, and the legal and institutional system matter for firm performance.

Technology and Market Structure

Abstract: This paper re-examines the relationship between the R&D intensity of an industry and its level of concentration, from the perspective of the Bounds approach to market structure. In so doing, it proposes an index which summarises those aspects of technology and tastes that are relevant to the determination of a lower bound to concentration.

Políticas públicas: uma revisão da literatura

Abstract: The article presents a review of the main concepts and models for making and assessment of public policies, seeking to synthesize the state of the art in the field, that is, to map how classic and more recent literature approach the subject. The article also seeks to discuss possibilities for application of distinct streams of neo-institutionalist theories to the assessment of public policies.

Media Literacy and the Challenge of New Information and Communication Technologies

Abstract: Within both academic and policy discourses, the concept of media literacy is being extended from its traditional focus on print and audiovisual media to encompass the internet and other new media. The present article addresses three central questions currently facing the public, policy-makers and academy: What is media literacy? How is it changing? And what are the uses of literacy? The article begins with a definition: media literacy is the ability to access, analyse, evaluate and create messages across a variety of contexts. This four-component model is then examined for its applicability to the internet. Having advocated this skills-based approach to media literacy in relation to the internet, the article identifies some outstanding issues for new media literacy crucial to any policy of promoting media literacy among the population. The outcome is to extend our understanding of media literacy so as to encompass the historically and culturally conditioned relationship among three processes: (i) the symb...