Epidemiological, social, diagnostic and economic evaluation of population screening for genital chlamydial infection

OBJECTIVES: To investigate epidemiological, social, diagnostic and economic aspects of chlamydia screening in non-genitourinary medicine settings. METHODS: Linked studies around a cross-sectional population-based survey of adult men and women invited to collect urine and (for women) vulvovaginal swab specimens at home and mail these to a laboratory for testing for Chlamydia trachomatis. Specimens were used in laboratory evaluations of an amplified enzyme immunoassay (PCE EIA) and two nucleic acid amplification tests [Cobas polymerase chain reaction (PCR), Becton Dickinson strand displacement amplification (SDA)]. Chlamydia-positive cases and two negative controls completed a risk factor questionnaire. Chlamydia-positive cases were invited into a randomised controlled trial of partner notification strategies. Samples of individuals testing negative completed psychological questionnaires before and after screening. In-depth interviews were conducted at all stages of screening. Chlamydia transmission and cost-effectiveness of screening were investigated in a transmission dynamic model. SETTING AND PARTICIPANTS: General population in the Bristol and Birmingham areas of England. In total, 19,773 women and men aged 16-39 years were randomly selected from 27 general practice lists. RESULTS: Screening invitations reached 73% (14,382/19,773). Uptake (4731 participants), weighted for sampling, was 39.5% (95% CI 37.7, 40.8%) in women and 29.5% (95% CI 28.0, 31.0%) in men aged 16-39 years. Chlamydia prevalence (219 positive results) in 16-24 year olds was 6.2% (95% CI 4.9, 7.8%) in women and 5.3% (95% CI 4.4, 6.3%) in men. The case-control study did not identify any additional factors that would help target screening. Screening did not adversely affect anxiety, depression or self-esteem. Participants welcomed the convenience and privacy of home-sampling. The relative sensitivity of PCR on male urine specimens was 100% (95% CI 89.1, 100%). The combined relative sensitivities of PCR and SDA using female urine and vulvovaginal swabs were 91.8% (86.1, 95.7, 134/146) and 97.3% (93.1, 99.2%, 142/146). A total of 140 people (74% of eligible) participated in the randomised trial. Compared with referral to a genitourinary medicine clinic, partner notification by practice nurses resulted in 12.4% (95% CI -3.7, 28.6%) more patients with at least one partner treated and 22.0% (95% CI 6.1, 37.8%) more patients with all partners treated. The health service and patients costs (2005 prices) of home-based postal chlamydia screening were 21.47 pounds (95% CI 19.91 pounds, 25.99) per screening invitation and 28.56 pounds (95% CI 22.10 pounds, 30.43) per accepted offer. Preliminary modelling found an incremental cost-effectiveness ratio (2003 prices) comparing screening men and women annually to no screening in the base case of 27,000 pounds/major outcome averted at 8 years. If estimated screening uptake and pelvic inflammatory disease incidence were increased, the cost-effectiveness ratio fell to 3700 pounds/major outcome averted. CONCLUSIONS: Proactive screening for chlamydia in women and men using home-collected specimens was feasible and acceptable. Chlamydia prevalence rates in men and women in the general population are similar. Nucleic acid amplification tests can be used on first-catch urine specimens and vulvovaginal swabs. The administrative costs of proactive screening were similar to those for opportunistic screening. Using empirical estimates of screening uptake and incidence of complications, screening was not cost-effective.

The coevolution of cooperation and dispersal in social groups and its implications for the emergence of multicellularity

Background Recent work on the complexity of life highlights the roles played by evolutionary forces at different levels of individuality. One of the central puzzles in explaining transitions in individuality for entities ranging from complex cells, to multicellular organisms and societies, is how different autonomous units relinquish control over their functions to others in the group. In addition to the necessity of reducing conflict over effecting specialized tasks, differentiating groups must control the exploitation of the commons, or else be out-competed by more fit groups. Results We propose that two forms of conflict – access to resources within groups and representation in germ line – may be resolved in tandem through individual and group-level selective effects. Specifically, we employ an optimization model to show the conditions under which different within-group social behaviors (cooperators producing a public good or cheaters exploiting the public good) may be selected to disperse, thereby not affecting the commons and functioning as germ line. We find that partial or complete dispersal specialization of cheaters is a general outcome. The propensity for cheaters to disperse is highest with intermediate benefit:cost ratios of cooperative acts and with high relatedness. An examination of a range of real biological systems tends to support our theory, although additional study is required to provide robust tests. Conclusion We suggest that trait linkage between dispersal and cheating should be operative regardless of whether groups ever achieve higher levels of individuality, because individual selection will always tend to increase exploitation, and stronger group structure will tend to increase overall cooperation through kin selected benefits. Cheater specialization as dispersers offers simultaneous solutions to the evolution of cooperation in social groups and the origin of specialization of germ and soma in multicellular organisms.

Variation of a test's sensitivity and specificity with disease prevalence

BACKGROUND Anecdotal evidence suggests that the sensitivity and specificity of a diagnostic test may vary with disease prevalence. Our objective was to investigate the associations between disease prevalence and test sensitivity and specificity using studies of diagnostic accuracy. METHODS We used data from 23 meta-analyses, each of which included 10-39 studies (416 total). The median prevalence per review ranged from 1% to 77%. We evaluated the effects of prevalence on sensitivity and specificity using a bivariate random-effects model for each meta-analysis, with prevalence as a covariate. We estimated the overall effect of prevalence by pooling the effects using the inverse variance method. RESULTS Within a given review, a change in prevalence from the lowest to highest value resulted in a corresponding change in sensitivity or specificity from 0 to 40 percentage points. This effect was statistically significant (p < 0.05) for either sensitivity or specificity in 8 meta-analyses (35%). Overall, specificity tended to be lower with higher disease prevalence; there was no such systematic effect for sensitivity. INTERPRETATION The sensitivity and specificity of a test often vary with disease prevalence; this effect is likely to be the result of mechanisms, such as patient spectrum, that affect prevalence, sensitivity and specificity. Because it may be difficult to identify such mechanisms, clinicians should use prevalence as a guide when selecting studies that most closely match their situation.

ANOVA kernels and RKHS of zero mean functions for model-based sensitivity analysis

Given a reproducing kernel Hilbert space (H,〈.,.〉)(H,〈.,.〉) of real-valued functions and a suitable measure μμ over the source space D⊂RD⊂R, we decompose HH as the sum of a subspace of centered functions for μμ and its orthogonal in HH. This decomposition leads to a special case of ANOVA kernels, for which the functional ANOVA representation of the best predictor can be elegantly derived, either in an interpolation or regularization framework. The proposed kernels appear to be particularly convenient for analyzing the effect of each (group of) variable(s) and computing sensitivity indices without recursivity.

Preservation and representation of human bones and it's importance for anthropological Analysis - an introduction

This paper presents problems arising from the lack of standardized methods for recording skeletal remains. Using practical examples it is shown how preservation and representation of bones can distort observations and how this can be reduced by systematic data acquisition.

Fuzzy Web Knowledge Aggregation, Representation, and Reasoning for Online Privacy and Reputation Management

A social Semantic Web empowers its users to have access to collective Web knowledge in a simple manner, and for that reason, controlling online privacy and reputation becomes increasingly important, and must be taken seriously. This chapter presents Fuzzy Cognitive Maps (FCM) as a vehicle for Web knowledge aggregation, representation, and reasoning. With this in mind, a conceptual framework for Web knowledge aggregation, representation, and reasoning is introduced along with a use case, in which the importance of investigative searching for online privacy and reputation is highlighted. Thereby it is demonstrated how a user can establish a positive online presence.

Gender-fair Language Changes the Social Perception of Professional Groups: The Case of German and Italian.

Gender-fair language, including women and men, such as word pairs has a substantial impact on the mental representation, as a large body of studies have shown. When using exclusively the masculine form as a generic, women are mentally significantly less represented than men. Word pairs, however, lead to a higher cognitive inclusion of women. Surprisingly little research has been conducted to understand how the perception of professional groups is affected by gender-fair language. Providing evidence from an Italian-Austrian cross-cultural study with over 400 participants, we argue that gender-fair language impacts the perception of professional groups, in terms of perceived gender-typicality, number of women and men assumed for a profession, social status and average income. Results hint at a pervasive pay-off: on the one hand, gender-fair language seems to boost the mental representations in favor of women and professions are perceived as being rather gender-neutral. On the other hand professional groups are assigned lower salary and social status with word pairs. Implications of results are discussed.

The significant effect of endometriosis on physical, mental and social wellbeing: results from an international cross-sectional survey.

STUDY QUESTION To what extent do the management of endometriosis and the symptoms that remain after treatment affect the quality of life in women with the disease? SUMMARY ANSWER Many women with endometriosis had impaired quality of life and continued to suffer from endometriosis-associated symptoms even though their endometriosis has been managed in tertiary care centres. WHAT IS KNOWN ALREADY The existing literature indicates that quality of life and work productivity is reduced in women with endometriosis. However, most studies have small sample sizes, are treatment related or examine newly diagnosed patients only. STUDY DESIGN, SIZE, DURATION A cross-sectional questionnaire-based survey among 931 women with endometriosis treated in 12 tertiary care centres in 10 countries. PARTICIPANTS/MATERIALS, SETTING, METHODS Women diagnosed with endometriosis who had at least one contact related to endometriosis-associated symptoms during 2008 with a participating centre were enrolled into the study. The study investigated the effect of endometriosis on education, work and social wellbeing, endometriosis-associated symptoms and health-related quality of life, by using questions obtained from the World Endometriosis Research Foundation (WERF) GSWH instrument (designed and validated for the WERF Global Study on Women's Health) and the Short Form 36 version 2 (SF-36v2). MAIN RESULTS AND THE ROLE OF CHANCE Of 3216 women invited to participate in the study, 1450 (45%) provided informed consent and out of these, 931 (931/3216 = 29%) returned the questionnaires. Endometriosis had affected work in 51% of the women and affected relationships in 50% of the women at some time during their life. Dysmenorrhoea was reported by 59%, dyspareunia by 56% and chronic pelvic pain by 60% of women. Quality of life was decreased in all eight dimensions of the SF-36v2 compared with norm-based scores from a general US population (all P < 0.01). Multivariate regression analysis showed that number of co-morbidities, chronic pain and dyspareunia had an independent negative effect on both the physical and mental component of the SF-36v2. LIMITATIONS, REASONS FOR CAUTION The fact that women were enrolled in tertiary care centres could lead to a possible over-representation of women with moderate-to-severe endometriosis, because the participating centres typically treat more complex and referred cases of endometriosis. The response rate was relatively low. Since there was no Institute Review Board approval to do a non-responder investigation on basic characteristics, some uncertainty remains regarding the representativeness of the investigated population. WIDER IMPLICATIONS OF THE FINDINGS This international multicentre survey represents a large group of women with endometriosis, in all phases of the disease, which increases the generalizability of the data. Women still suffer from frequent symptoms, despite tertiary care management, in particular chronic pain and dyspareunia. As a result their quality of life is significantly decreased. A patient-centred approach with extensive collaboration across disciplines, such as pain specialists, psychologists, sexologists and social workers, may be a valuable strategy to improve the long-term care of women with endometriosis. STUDY FUNDING/COMPETING INTEREST(S) The WERF EndoCost study is funded by the World Endometriosis Research Foundation (WERF) through grants received from Bayer Schering Pharma AG, Takeda Italia Farmaceutici SpA, Pfizer Ltd and the European Society of Human Reproduction and Embryology. The sponsors did not have a role in the design and conduct of the study; collection, management, analysis and interpretation of the data; and preparation, review or approval of the manuscript. L.H. is the chief executive and T.D. was a board member of WERF at the time of funding. T.D. holds the Merck-Serono Chair in Reproductive Medicine and Surgery, and the Ferring Chair in Reproductive Medicine at the Katholieke Universiteit Leuven in Belgium and has served as consultant/research collaborator for Merck-Serono, Schering-Plough, Astellas and Arresto.

Transgressive sporting bodies - A theoretical and critical dicourse analysis of the representation of Caster Semenya in Swiss print media

A debate about Caster Semenya's female sex began shortly after the South African runner won gold in the women’s 800m final at the 2009 Athletic World Championships held in Berlin. Her victory was disputed through questions about her right to compete as a ‘woman’, with the International Association of Athletics Federation (IAAF) announcing she would be required to undergo a gender verification test before her victory could be confirmed. Using the theoretical frame of social constructionism (Berger & Luckmann), poststructuralism (Foucault), gender- and postcolonial theories (Butler; Hall; Spivak) and the methodology of critical discourse analysis (Jaeger), the paper explores the way the possible intersexuality of Caster Semenya was contextualised in mainstream Swiss German-language print media. The analyses will firstly look at the way in which Caster Semenya was constructed as a ʻfallen hero’ and stigmatised as a double-dealer and unacceptable deviant body. The rumours amongst athletes and commentators became news in the media, which focused on descriptions of her habitus, her muscular body and her deep voice. Through theoretical discussion the paper argues that the media response to Caster Semenya exemplifies Butler’s claim that the discursive framework of gender constructs and naturalises sex. A key question is therefore whether the designation of deviant bodies to a ʻfield of deformation’ (Butler) works to pluralise the field of gender, or rather, as Butler suggests, it tends that those bodies might call into questions. The final part of the paper discusses how gender, ethnicity and sexuality combine to constitute the black female sporting body as a spectacle of otherness. It is evident that this otherness is made manifest through the function of those bodies as a site of transgression, as the boundary between male and female, and often as the boundary between culture and nature (Hall). Using the example of the controversy surrounding Caster Semenya, this paper aims to demonstrate how the post/colonial white female body is reproduced by western norms of gender, sexuality, beauty and sporting behaviour, in the sense of a feminine sporting genderperformance. The media controversy will be also read through the lens of the globalisation of certain ideas of normative bodies, sex, ethnicity and gender and the challenge of changing stereotypes through transgression. Keywords: gender- and postcolonial theories, discourse analysis, print media, Caster Semen-ya, deviant body, ethnicity, intersexuality

Transgressive sporting bodies - A theoretical and critical dicourse analysis of the representation of Caster Semenya in Swiss print media

A debate about Caster Semenya's female sex began shortly after the South African runner won gold in the women’s 800m final at the 2009 Athletic World Championships held in Berlin. Her victory was disputed through questions about her right to compete as a ‘woman’, with the International Association of Athletics Federation (IAAF) announcing she would be required to undergo a gender verification test before her victory could be confirmed. Using the theoretical frame of social constructionism (Berger & Luckmann), poststructuralism (Foucault), gender- and postcolonial theories (Butler; Hall; Spivak) and the methodology of critical discourse analysis (Jaeger), the paper explores the way the possible intersexuality of Caster Semenya was contextualised in mainstream Swiss German-language print media. The analyses will firstly look at the way in which Caster Semenya was constructed as a ʻfallen hero’ and stigmatised as a double-dealer and unacceptable deviant body. The rumours amongst athletes and commentators became news in the media, which focused on descriptions of her habitus, her muscular body and her deep voice. Through theoretical discussion the paper argues that the media response to Caster Semenya exemplifies Butler’s claim that the discursive framework of gender constructs and naturalises sex. A key question is therefore whether the designation of deviant bodies to a ʻfield of deformation’ (Butler) works to pluralise the field of gender, or rather, as Butler suggests, it tends that those bodies might call into questions. The final part of the paper discusses how gender, ethnicity and sexuality combine to constitute the black female sporting body as a spectacle of otherness. It is evident that this otherness is made manifest through the function of those bodies as a site of transgression, as the boundary between male and female, and often as the boundary between culture and nature (Hall). Using the example of the controversy surrounding Caster Semenya, this paper aims to demonstrate how the post/colonial white female body is reproduced by western norms of gender, sexuality, beauty and sporting behaviour, in the sense of a feminine sporting genderperformance. The media controversy will be also read through the lens of the globalisation of certain ideas of normative bodies, sex, ethnicity and gender and the challenge of changing stereotypes through transgression. Keywords: gender- and postcolonial theories, discourse analysis, print media, Caster Semen-ya, deviant body, ethnicity, intersexuality