Permutation tests of scale using deviances

Robust tests for comparing scale parameters, based on deviances—absolute deviations from the median—are examined. Higgins (2004) proposed a permutation test for comparing two treatments based on the ratio of deviances, but the performance of this procedure has not been investigated. A simulation study examines the performance of Higgins’ test relative to other tests of scale utilizing deviances that have been shown in the literature to have good properties. An extension of Higgins’ procedure to three or more treatments is proposed, and a second simulation study compares its performance to other omnibus tests for comparing scale. While no procedure emerged as a preferred choice in every scenario, Higgins’ tests are found to perform well overall with respect to Type I error rate and power.     

Cross-national Comparison of the Quality of Life in Europe: Inventory of Surveys and Methods

The intention of this paper is to provide thescientific community with information onresearch carried out in the course of thecomparative research programme EuReporting – Towards a European System onSocial Reporting and Welfare Measurement. Thisresearch is being funded by the EuropeanCommission and is being conducted by researchteams throughout Europe. In this paper, we willreport on the findings of the research carriedout by the team in Vienna. The Vienneseresearch team is to assess the existing stockof comparative and cross-sectional surveys inthe field of social reporting and welfaremeasurement. Of concern here is not onlydocumentary work, but also the quality andcomparability of existing survey data. Thefocus of the Vienna project is upon suchcross-national and cross-sectional surveys asthe World Values Survey, the InternationalSocial Survey Programme, the Eurobarometer andthe New Democracies Barometer, as well asnational longitudinal studies.     

In-migration and Living Conditions of Young Adolescents in Greater Johannesburg, South Africa

While migration in South Africa has been studied on a broad canvas, there have been few accounts of children's migration and the effects on living conditions and wellbeing. This article compares the access to services, housing and household amenities, and family characteristics of children born in the Greater Johannesburg metropolis with those of in-migrant children. The article also examines other indicators of child wellbeing related to parental care and schooling. In-migrant children, particularly children who have lived previously in rural areas and/or have recently migrated into the city, are significantly disadvantaged in comparison to long-term resident children in terms of parental education and occupation, housing type and ownership, access to electricity, refuse removal, water and sanitation. In-migrant children also live in households that are less likely to have amenities such as a refrigerator, television, washing machine, telephone and motor vehicle. In terms of child indicators, in-migrant children enjoy less frequent parental contact and are twice as likely to start school later than resident children. Whilst urbanisation to South Africa's metropolitan centres is generally associated with several widely recognised benefits, for children, these benefits may be tempered by the disadvantages of in-migrant families known to be associated with child wellbeing.     

Distributional implications of equal sacrifice rules

A conclusive story can be made out of equal absolute and equal proportional sacrifice rules if only income after some poll tax of equal total revenue is taken as basis for distributional comparisons.     

Field Measurement of Dermal Soil Loading Attributable to Various Activities: Implications for Exposure Assessment

Estimates of soil adherence to skin are required for assessment of dermal exposures to contaminants in soils. Previously available estimates depend heavily on indirect measurements and/or artificial activities and reflect sampling of hands only. Results are presented here from direct measurement of soil loading on skin surfaces of volunteers before and after normal occupational and recreational activities that might reasonably be expected to lead to soil contact. Skin surfaces assayed included hands, forearms, lower legs, faces and/or feet. Observed hand loadings vary over five orders of magnitude (roughly from 10^–3 to 10² mg/cm²) and are dependent upon type of activity. Hand loadings within the current default range of 0.2 to 1.0 mg/cm² were produced by activities providing opportunity for relatively vigorous soil contact (rugby, farming). Loadings less than 0.2 mg/cm² were found on hands following activities presenting less opportunity for direct soil contact (soccer, professional grounds maintenance) and on other body parts under many conditions. The default range does not, however, represent a worst case. Children playing in mud on the shore of a lake generated geometric mean loadings well in excess of 1 mg/cm² on hands, arms, legs, and feet. Post-activity average loadings on hands were typically higher than average loadings on other body parts resulting from the same activity. Hand data from limited activities cannot, however, be used to conservatively predict loadings that might occur on other body surfaces without regard to activity since non-hand loadings attributable to higher contact activities exceeded hand loadings resulting from lower contact activities. Differences between pre- and post-activity loadings also demonstrate that dermal contact with soil is episodic. Typical background (pre-activity) geometric mean loadings appear to be on the order of 10^-2 mg/cm² or less. Because exposures are activity dependent, quantification of dermal exposure to soil will remain inadequate until data describing relevant human behavior (type of activity, frequency, duration including interval before bathing, clothing worn, etc.) are generated.     

An evaluation study of a health education programme for rural women in Bangladesh

In the 1980s, 21 Health and Family Welfare Centres (HFWC) in Munchiganz district in Bangladesh extended health and family planning services and health education to satellite clinics in private homes. A family welfare visitor (FWV) would visit each clinic 2 times/week to conduct health education sessions and treat patients. HFWC also promoted 70 mothers' clubs to promote small family size. Some mothers' clubs even provide basic health services. In March 1985, HFWC designed a study to evaluate the effectiveness of its health education component. Interviews and observations constituted the methodologies used. Interviewers and staff who were to observe health education lessons attended an introductory workshop in which they designed questionnaires. Next participant conducted 1-2 interviews while doing their regular work to pilot test the questionnaires. They then went to another workshop where they received feedback and discussed problems before the main evaluation. The study coordinator made spot check observations while interviewers spoke with women after a session on safe childbirth or diarrhea. The coordinator also held weekly meetings with the interviewers to identify problems and maintain a common base. HFWC managers used the study results to design and implement a simple monitoring system, manageable by supervisors, and others in the same or in a similar position. A very important lesson learned was that any monitoring system should not disrupt the routine of regular supervisory work or the already tight working schedules. The system should be uncomplicated so supervisors can easily monitor the health education component. Finally monitoring standards need to be founded on a common understanding and feedback between planners and health educators.     

Integrating phase 2 into phase 3 based on an intermediate endpoint while accounting for a cure proportion—With an application to the design of a clinical trial in acute myeloid leukemia

For a trial with primary endpoint overall survival for a molecule with curative potential, statistical methods that rely on the proportional hazards assumption may underestimate the power and the time to final analysis. We show how a cure proportion model can be used to get the necessary number of events and appropriate timing via simulation. If phase 1 results for the new drug are exceptional and/or the medical need in the target population is high, a phase 3 trial might be initiated after phase 1. Building in a futility interim analysis into such a pivotal trial may mitigate the uncertainty of moving directly to phase 3. However, if cure is possible, overall survival might not be mature enough at the interim to support a futility decision. We propose to base this decision on an intermediate endpoint that is sufficiently associated with survival. Planning for such an interim can be interpreted as making a randomized phase 2 trial a part of the pivotal trial: If stopped at the interim, the trial data would be analyzed, and a decision on a subsequent phase 3 trial would be made. If the trial continues at the interim, then the phase 3 trial is already underway. To select a futility boundary, a mechanistic simulation model that connects the intermediate endpoint and survival is proposed. We illustrate how this approach was used to design a pivotal randomized trial in acute myeloid leukemia and discuss historical data that informed the simulation model and operational challenges when implementing it.