Emergency contraceptive pills: a 10-year follow-up survey of use and experiences at college health centers in the mid-Atlantic United States

The authors conducted a 10-year follow-up study using a telephone survey to investigate the availability of emergency contraceptive pills (ECPs) at college health centers in the mid-Atlantic region of the United States. They also examined related issues, such as distribution procedure, existence of a written protocol, personnel involved, contraindications, follow-up procedures, methods of advertising, staff attitudes, changes in distribution over the past 10 years, and availability if ECPs become over-the-counter. Of the 119 completed responses, 58 schools (49%) reported distributing ECPs. The most common reasons schools listed for not distributing ECPs (n = 61, 51%) were religious convictions, understaffing, and lack of funding. Major changes in ECP distribution over the past 10 years related primarily to the number of schools distributing ECPs, protocol in ECP distribution, and advertising for ECP services.     

Predictors of falling in older Maryland drivers: a structural-equation model

Falls can impair health and reduce quality of life among older adults. Although many factors are related to falling, few analyses examine causal models of this behavior. In this study, factors associated with falling were explored simultaneously using structural-equation modeling. A variety of cognitive, physical-performance, and health measures were administered to 694 older adult drivers from the state of Maryland. The observed and latent variables of age, cognitive ability, physical functioning, health, and falling behavior were used to create a causal model. The model revealed that being older was associated with declines in cognition, and such cognitive declines predicted increased falling. Similarly, poorer health was related to poorer physical functioning, which, in turn, also predicted increased falling. This model indicates that in addition to existing fall-prevention interventions aimed at improving physical functioning, interventions to improve cognition and health might also be effective. It is speculated that fear of falling, which often results in reduced mobility among older adults, might account for the lack of a direct relationship between age and falling. This hypothesis should be examined in further research.     

Lessons from Drosophila models of DJ-1 deficiency

Mutations in the DJ-1 gene are associated with rare forms of autosomal recessive early-onset Parkinson's disease (PD). Although the precise physiological function of DJ-1 remains obscure, accumulating evidence suggests that DJ-1 may normally function as a redox-sensitive molecular chaperone that can protect against the deleterious effects of oxidative stress, particularly in mitochondria. Recent studies in the fruit fly, Drosophila melanogaster, have shed further light on the biological role of DJ-1. DJ-1-deficient Drosophila models exhibit distinct phenotypes but collectively highlight a prominent neuroprotective role for DJ-1 against oxidative insult. However, Drosophila lacking DJ-1 do not consistently produce a useful PD-like phenotype (that is, they generally fail to exhibit degeneration of neurons that contain the neurotransmitter dopamine), which may reflect putative compensatory neuroprotective mechanisms. DJ-1-deficient fly models further highlight the utility of Drosophila as an important tool for elucidating protein function and for modeling neurodegenerative disease.     

A Bayesian approach to statistical inference in stochastic DEA

Stochastic DEA can deal effectively with noise in the non-parametric measurement of efficiency but unfortunately formal statistical inference on efficiency measures in not possible. In this paper, we provide a Bayesian approach to the problem organized around simulation techniques that allow for finite-sample inferences on efficiency scores. The new methods are applied to efficiency analysis of the Greek banking system for the period 1993–1999. The results show that the majority of the Greek banks operate close to best market practices.     

Prüfungshonorare in Deutschland – Determinanten und Implikationen

The audit fees available since 2005 as a consequence of the Bilanzrechtsreformgesetz (commercial code reform act) show an extremely high supplier concentration on the German audit market of publicly listed companies. This justifies the assumption of audit fees above perfect market equilibrium prices. However, the complete collection and multivariate regression analysis of all relevant audit fee and client data document a 24 % decrease in audit fees in 2005 and an average 15 % decrease in the two subsequent years due to auditor changes. This can be interpreted as an indicator for price competition. In addition, the audit fee data shows that the audit fee decreases are only partially compensated by subsequent increases. As a consequence, there is no evidence for lowballing at present. Further time series are necessary to show if the current trend is sustainable.     

A Paradox for the “Smooth Ambiguity” Model of Preference

Two Ellsberg‐style thought experiments are described that reflect on the smooth ambiguity decision model developed by Klibanoff, Marinacci, and Mukerji (2005). The first experiment poses difficulties for the model's axiomatic foundations and, as a result, also for its interpretation, particularly for the claim that the model achieves a separation between ambiguity and the attitude toward ambiguity. Given the problematic nature of its foundations, the behavioral content of the model and how it differs from multiple priors, for example, are not clear. The second thought experiment casts some light on these questions.     

An interesting property of the Poisson operating characteristic function

In elementary probability theory, as a result of a limiting process the probabilities of aBi(n, p) binomial distribution are approximated by the probabilities of aPo(np) Poisson distribution. Accordingly, in statistical quality control the binomial operating characteristic function \(\mathcal{L}_{n,c} (p)\) is approximated by the Poisson operating characteristic function \(\mathcal{F}_{n,c} (p)\) . The inequality \(\mathcal{L}_{n + 1,c + 1} (p) > \mathcal{L}_{n,c} (p)\) forp∈(0;1) is evident from the interpretation of \(\mathcal{L}_{n + 1,c + 1} (p)\) , \(\mathcal{L}_{n,c} (p)\) as probabilities of accepting a lot. It is shown that the Poisson approximation \(\mathcal{F}_{n,c} (p)\) preserves this essential feature of the binomial operating characteristic function, i.e. that an analogous inequality holds for the Poisson operating characteristic function, too.     

Sequential and Simultaneous Decision Making for Optimizing Health Care Resource Flexibilities

Health care administrators commonly employ two types of resource flexibilities (demand upgrades and staffing flexibility) to efficiently coordinate two critical internal resources, nursing staff and beds, and an external resource (contract nurses) to satisfy stochastic patient demand. Under demand upgrades, when beds are unavailable for patients in a less acute unit, patients are upgraded to a more acute unit if space is available in that unit. Under staffing flexibility, nurses cross‐trained to work in more than one unit are used in addition to dedicated and contract nurses. Resource decisions (beds and staffing) can be made at a single point in time (simultaneous decision making) or at different points in time (sequential decision making). In this article, we address the following questions: for each flexibility configuration, under sequential and simultaneous decision making, what is the optimal resource level required to meet stochastic demand at minimum cost? Is one type of flexibility (e.g., demand upgrades) better than the other type of flexibility (e.g., staffing flexibility)? We use two‐stage stochastic programming to find optimal resource levels for two nonhomogeneous hospital units that face stochastic demand following a continuous, general distribution. We conduct a full‐factorial numerical experiment and find that the benefit of using staffing flexibility on average is greater than the benefit of using demand upgrades. However, the two types of flexibilities have a positive interaction effect and they complement each other. The type of flexibility and decision timing has an independent effect on system performance (capacity and staffing costs). The benefits of cross‐training can be largely realized even if beds and staffing levels have been determined prior to the establishment of a cross‐training initiative.