On the absolute calibration of bench-top small-angle X-ray scattering instruments: a comparison of different standard methods

Absolute calibration relates the measured (arbitrary) intensity to the differential scattering cross section of the sample, which contains all of the quantitative information specific to the material. The importance of absolute calibration in small-angle scattering experiments has long been recognized. This work details the absolute calibration procedure of a small-angle X-ray scattering instrument from Bruker AXS. The absolute calibration presented here was achieved by using a number of different types of primary and secondary standards. The samples were: a glassy carbon specimen, which had been independently calibrated from neutron radiation; a range of pure liquids, which can be used as primary standards as their differential scattering cross section is directly related to their isothermal compressibility; and a suspension of monodisperse silica particles for which the differential scattering cross section is obtained from Porod's law. Good agreement was obtained between the different standard samples, provided that care was taken to obtain significant signal averaging and all sources of background scattering were accounted for. The specimen best suited for routine calibration was the glassy carbon sample, due to its relatively intense scattering and stability over time; however, initial calibration from a primary source is necessary. Pure liquids can be used as primary calibration standards, but the measurements take significantly longer and are, therefore, less suited for frequent use.

I don't see me like you see me, but is that a problem? Cultural influences on rating discrepancy in 360-degree feedback instruments

360-degree feedback from a variety of rater sources yields important information about leaders' styles, strengths and weaknesses for development. Results where observer ratings are discrepant (i.e., different) from self-ratings are often seen as indicators of problematic leadership relationships, skills, or lack of self-awareness. Yet research into the antecedents of such self-observer rating discrepancy suggests the presence of systematic influences, such as cultural values. The present study investigates the variation of rating discrepancies on three leadership skills (decision making, leading employees, and composure) in dependence of one exemplary culture dimension (power distance) on data from 31 countries using multilevel structural equation modelling. Results show that cultural values indeed predict self-observer rating discrepancies. Thus, systemic and contextual influences such as culture need to be taken into consideration when interpreting the importance and meaning of self-observer rating discrepancies in 360-degree instruments.

Factors affecting e-payment adoption in Nigeria

The payment system of a country plays a crucial role in its economy; however, despite the benefits of e-Payment and efforts by financial authorities, Nigeria still has a low e-Payment adoption rate. In this regard, there is an urgent need to investigate the factors that affect individuals’ intention to adopt e-Payment. Drawing on the unified theory of acceptance and use of technology (UTAUT) model, this paper develops a theoretical model for e-Payment adoption in Nigeria. Additionally, a survey was conducted on 500 respondents with 213 complete responses received to test the model, and results show that perceived benefits, effort expectancy, social influence, trust, awareness, and demographic variables affected individuals’ intention to adopt e-Payments. Based on the findings, managerial and theoretical implications are deliberated.

Factors affecting e-payment adoption in Nigeria

For e-commerce to be successful, an efficient e-payment system is the key. The use of formal payment systems also enhances the ability to execute and manage monetary policies, which is essential for a country’s financial sector. Although Nigeria is a regional leader, the usage of e-Payments is still very low despite its many benefits and also attempts by the financial authorities. This therefore calls for an urgent need to investigate the factors that affect individual’s intention to adopt e-payment in Nigeria so that steps can be fashioned out to improve the situation. A survey was conducted to get individual perceptions of e-payments through the use of questionnaires designed based on the theoretical model developed. The results showed that awareness, knowledge of benefits, ease of use, reliability, trust and security, acceptability, accessibility and social influence are the main factors that influence individuals’ intention to adopt e-payments.

Has DRG payment influenced the technical efficiency and productivity of diagnostic technologies in Portuguese public hospitals? An empirical analysis using parametric and non‐parametric methods

The use of Diagnosis Related Groups (DRG) as a mechanism for hospital financing is a currently debated topic in Portugal. The DRG system was scheduled to be initiated by the Health Ministry of Portugal on January 1, 1990 as an instrument for the allocation of public hospital budgets funded by the National Health Service (NHS), and as a method of payment for other third party payers (e.g., Public Employees (ADSE), private insurers, etc.). Based on experience from other countries such as the United States, it was expected that implementation of this system would result in more efficient hospital resource utilisation and a more equitable distribution of hospital budgets. However, in order to minimise the potentially adverse financial impact on hospitals, the Portuguese Health Ministry decided to gradually phase in the use of the DRG system for budget allocation by using blended hospitalspecific and national DRG casemix rates. Since implementation in 1990, the percentage of each hospitals budget based on hospital specific costs was to decrease, while the percentage based on DRG casemix was to increase. This was scheduled to continue until 1995 when the plan called for allocating yearly budgets on a 50% national and 50% hospitalspecific cost basis. While all other nonNHS third party payers are currently paying based on DRGs, the adoption of DRG casemix as a National Health Service budget setting tool has been slower than anticipated. There is now some argument in both the political and academic communities as to the appropriateness of DRGs as a budget setting criterion as well as to their impact on hospital efficiency in Portugal. This paper uses a twostage procedure to assess the impact of actual DRG payment on the productivity (through its components, i.e., technological change and technical efficiency change) of diagnostic technology in Portuguese hospitals during the years 1992–1994, using both parametric and nonparametric frontier models. We find evidence that the DRG payment system does appear to have had a positive impact on productivity and technical efficiency of some commonly employed diagnostic technologies in Portugal during this time span.

Quality of life instruments in studies of menorrhagia: a systematic review

BACKGROUND: The use of quality of life (QoL) instruments in menorrhagia research is increasing but there is concern that not enough emphasis is placed on patient-focus in these measurements, i.e. on issues which are of importance to patients and reflect their experiences and concerns (clinical face validity). The objective was to assess the quality of QoL instruments in studies of menorrhagia. STUDY DESIGN: A systematic review of published research. Papers were identified through MEDLINE (1966-April 2000), EMBASE (1980-April 2000), Science Citation Index (1981-April 2000), Social Science Citation Index (1981-April 2000), CINAHL (1982-1999) and PsychLIT (1966-1999), and by manual searching of bibliographies of known primary and review articles. Studies were selected if they assessed women with menorrhagia for life quality, either developing QoL instruments or applying them as an outcome measure. Selected studies were assessed for quality of their QoL instruments, using a 17 items checklist including 10 items for clinical face validity (issues of relevance to patients' expectations and concerns) and 7 items for measurement properties (such as reliability, responsiveness, etc.). RESULTS: A total of 19 articles, 8 on instrument development and 11 on application, were included in the review. The generic Short Form 36 Health Survey Questionnaire (SF36) was used in 12/19 (63%) studies. Only two studies developed new specific QoL instruments for menorrhagia but they complied with 7/17 (41%) and 10/17 (59%) of the quality criteria. Quality assessment showed that only 7/19 (37%) studies complied with more than half the criteria for face validity whereas 17/19 (90%) studies complied with more than half of the criteria for measurement properties (P = 0.0001). CONCLUSION: Among existing QoL instruments, there is good compliance with the quality criteria for measurement properties but not with those for clinical face validity. There is a need to develop methodologically sound disease specific QoL instruments in menorrhagia focussing both on face validity and measurement properties.