A case study in identifying targeted patients population in major depressive disorder by enhanced enrichment design

Despite advances in clinical trial design, failure rates near 80% in phase 2 and 50% in phase 3 have recently been reported. The challenges to successful drug development are particularly acute in central nervous system trials such as for pain, schizophrenia, mania, and depression because high‐placebo response rates lessen assay sensitivity, diminish estimated treatment effect sizes, and thereby decrease statistical power. This paper addresses the importance of rigorous patient selection in major depressive disorder trials through an enhanced enrichment paradigm. This approach led to a redefinition of an ongoing, blinded phase 3 trial algorithm for patient inclusion (1) to eliminate further randomization of transient placebo responders and (2) to exclude previously randomized transient responders from the primary analysis of the double blind phase of the trial. It is illustrated for a case study for the comparison between brexpiprazole + antidepressant therapy and placebo + antidepressant therapy. Analysis of the primary endpoint showed that efficacy of brexpiprazole versus placebo could not be established statistically if the original algorithm for identification of placebo responders was used, but the enhanced enrichment approach did statistically demonstrate efficacy. Additionally, the enhanced enrichment approach identified a target population with a clinically meaningful treatment effect. Through its successful identification of a target population, the innovative enhanced enrichment approach enabled the demonstration of a positive treatment effect in a very challenging area of depression research.     

Setups and effective capacity: the impact of lot sizing techniques in an MRP environment

This study investigates how lot sizing techniques influence the profit performance, inventory level, and order lardiness of an assembly job shop controlled by MRP. Four single-level lot sizing techniques are compared by simulation analysis under two levels of master schedule instability and two levels of end item demand. A second analysis investigates the influence of a multilevel lot sizing technique, the generalized constrained-K (GCK) cost modification, on the four single-level techniques at low demand and low nervousness. The analyses reveal a previously unreported phenomenon. Given the same inventory costs, the single-level lot sizing techniques generate substantially different average batch sizes. The lot sizing techniques maintain the following order of increasing average batch size (and decreasing total setup time):

economic order quantity (EOQ)

period order quantity (POQ)

least total cost (LTC)

Silver-Meal heuristic (SML)

The causes for different average batch sizes among the lot sizing techniques are analysed and explained. Demand lumpiness, inherent in multilevel manufacturing systems controlled by MRP, is found to be a major factor. The number of setups each lot sizing technique generates is the primary determinant of profit performance, inventory level, and order tardiness. EOQ, a fixed order quantity technique, is less sensitive to nervousness than the discrete lot sizing techniques. EOQ_, however, generates the smallest average batch size, and, therefore, the most setups. Since setups consume capacity, EOQ, is more sensitive to higher demand. SML generates the largest average batch sizes, and is, therefore, less sensitive to increased demand. At low demand, the other lot sizing techniques perform better on all criteria. They generate smaller batches and, therefore, shorter actual lead times. The GCK cost modification increases the average batch size generated by each lot sizing technique. GCK improves the profit and customer service level of EOQ the lot sizing technique with the smallest batches. GCK causes the other lot sizing techniques to generate excessively large batches and, therefore, excessively long actual lead times.     

Evaluation of a class-based storage scheduling technique applied to dual-shuttle automated storage and retrieval systems

Research to improve the performance of automated storage and retrieval systems has concentrated on developing more effective system designs or scheduling control programs to reduce the time a shuttle spends travelling in a rack. Sarker et al. (1991) showed that a dual-shuttle AS/RS operating under a nearest-neighbour scheduling model would significantly improve system throughput performance over a single-load shuttle system. The study was limited in that it only considered dual-shuttle improvements under the nearest-neighbour model. This research exploits the benefits of a dual-shuttle system by integrating the technology with a more effective scheduling technique, the class-based storage model, for reducing the shuttle travel time. The dual-shuttle, class-based storage model produced a significant reduction in shuttle travel time and thus higher throughput results over the dual-shuttle, nearest-neighbour model. This study further supports the premise that a dual-capacity shuttle is an effective way of improving the productivity of an automated storage and retrieval system.     

Is religion a health resource for the poor?

This paper uses data from the 2004 General Social Survey to examine the relationship between religious belief and practice (religiosity), spirituality, social support, and health status. Health status is conceptualized first in terms of a subjective assessment and, second, as two objective indicators of physical problems. These relationships were examined first within the total GSS sample, and then separately for respondents who reported below or above the median annual income. Results indicate that spirituality is a positive predictor of respondents’ subjective assessment of their health in the overall sample, but not in either separate income group. Social support does not predict positive subjective or objective health outcomes in the entire sample or for any income group. However, religiosity is a positive predictor of physical health, but only for the most severe of the physical health problems measured, and only for respondents whose annual income is below the national median. Thus, it appears that religiosity is a health resource for those below average income.     

Eigenverantwortung — Berufliche Leistung und Anforderung

Ohne Zusammenfassung     

Impact of the reversal of the migration situation on the social structures of certain countries: the case of Italy

During the past 20 years, Italy has changed from being a country with well-established traditions of emigration to a country of destination. Italy had achieved 1 of the highest economic growth rates in the world. Conditions in Italy are favorable for hundreds of thousands of immigrants from developing countries. Most immigrants settle in large cities and in the South; most are in Italy illegally, performing jobs which Italians do not want. The Act n.943 of January 27, 1987, 1 of the most advanced and most liberal unilateral legal texts has 2 sections: 1) the 1st section establishes regulations governing the admission and residence of foreigners and conditions under which they may enter employment and 2) the 2nd section concerns the regularization of all situations involving the illegal presence of the hundreds of thousands of workers who arrived in Italy before 1987. During the 1st year of implementation, the Act proved to be ideologically enviable but unsuitable in practice. Specifically, Italian consulates in developing countries have received very few applications for permanent residence permits, while clandestine immigration is continuing. Also, only about 14% of clandestine immigrants who arrived before 1987 have regularized their situations. Insufficient information and excessive red tape in the regularization procedures contributed to these results. However, the fundamental cause of failure is economic: migrants know that regularization would keep them out of the labor market and be followed by loss of job and unemployment. Italians are uninterested in the role of immigrants as new members of society; the migrants, in turn, do everything possible not to draw attention to their presence and their diversity. Still, most Italians view immigrants with suspicion. To prepare for the future, account must be taken of possible fluctuations in the economic situation of expanding receiving countries and of the impact which these fluctuations may have on the degree of acceptance of immigrants. To solve these problems Italy must, 1) have a rational, realistic, and comprehensive approach to medium-term planning;2) use official development assistance to carry out labor-intensive projects in the partner country, to reduce the pressure to migrate; 3) base the planning of migration policy on the establishment of admission criteria for immigrants; 4) treat immigrants fairly and promote integration that respects their cultural identity; and 5) achieve international and multilateral coordination and consultation for migration policies.     

PAID- VERSUS DONATED-MEDIA STRATEGIES FOR PUBLIC SERVICE ANNOUNCEMENT CAMPAIGNS

Public service announcement (PSA) campaigns have traditionallyrelied on donated rather than paid advertising media. Recently,however, both government agencies and charitable or ganizationshave questioned whether donated-media strategies should be abandonedfor paid-media PSA campaigns. The present research examinesthis issue in a three-market field experiment comparing theeffectiveness of "paid versus donated" PSA cam paigns in decreasingyouthful male drinking and driving. Depen dent variables include(1) self-reports of behaviors from sample surveys and (2) officialcounts of incapacitating and fatal highway accidents. Resultsshow that both campaigns were equally effec tive and both werecost efficient. Thus, in light of these results, it is recommendedthat social marketers not abandon donated-media PSA campaignsfor paid-media PSA campaigns.     

MEASURING CRACK COCAINE AND ITS IMPACT

Numerous social indicators turned negative for Blacks in the 1980s and rebounded a decade later. We explore whether crack cocaine explains these patterns. Absent a direct measure, we construct a crack prevalence index using multiple proxies. Our index reproduces spatial and temporal patterns described in ethnographic accounts of the crack epidemic. It explains much of the 1980s rise in Black youth homicide and more moderate increases in adverse birth outcomes. Although our index remains high through the 1990s, crack's deleterious social impact fades. Changes over time in behavior, crack markets, and the user population may have mitigated crack's damaging impacts. (JEL K42, J15, I30)     

Analysis of bivariate dichotomous data from a stratified two-stage cluster sample

In the health and social sciences, researchers often encounter categorical data for which complexities come from a nested hierarchy and/or cross-classification for the sampling structure. A common feature of these studies is a non-standard data structure with repeated measurements which may have some degree of clustering. In this paper, methodology is presented for the joint estimation of quantities of interest in the context of a stratified two-stage sample with bivariate dichotomous data. These quantities are the mean value π of an observed dichotomous response for a certain condition or time-point and a set of correlation coefficients for intra-cluster association for each condition or time period and for inter-condition correlation within and among clusters. The methodology uses the cluster means and pairwise joint probability parameters from each cluster. They together provide appropriate information across clusters for the estimation of the correlation coefficients.     

The determinants of opting for the German group taxation regime with regard to taxes on corporate profits

Forming a tax group for corporate and trade tax purposes in Germany has its advantages in terms of tax savings for the companies concerned. Depending on the profit situation, for certain companies these benefits were extended by the 2001 German corporate tax reform. However, setting up a tax group in Germany is also accompanied by certain disadvantages for the consolidated companies, resulting especially from the assumption of increased liability for subsidiaries’ losses. The objective of this study is to investigate the factors determining the decision in favour of, or against, the formation of a tax group. A natural experiment arising from the 2001 German corporate tax reform allowed us to determine to what extent companies exploited the increased potential benefits of a tax group post reform. We test this finding employing firm-level data from the database AMADEUS. Our results show that the number of tax groups increased significantly with the introduction of the exemption method as from 01.01.2001. This result is especially apparent amongst companies benefiting from a tax group only post reform. Yet eligible companies which would have obtained tax benefits by entering into a tax group did not always choose this option. This applies in particular to parent companies with subsidiaries that are not wholly owned, and to small subsidiaries.