Using a NPWE model observer to assess suitable image quality for a digital mammography quality assurance programme.

A method of objectively determining imaging performance for a mammography quality assurance programme for digital systems was developed. The method is based on the assessment of the visibility of a spherical microcalcification of 0.2 mm using a quasi-ideal observer model. It requires the assessment of the spatial resolution (modulation transfer function) and the noise power spectra of the systems. The contrast is measured using a 0.2-mm thick Al sheet and Polymethylmethacrylate (PMMA) blocks. The minimal image quality was defined as that giving a target contrast-to-noise ratio (CNR) of 5.4. Several evaluations of this objective method for evaluating image quality in mammography quality assurance programmes have been considered on computed radiography (CR) and digital radiography (DR) mammography systems. The measurement gives a threshold CNR necessary to reach the minimum standard image quality required with regards to the visibility of a 0.2-mm microcalcification. This method may replace the CDMAM image evaluation and simplify the threshold contrast visibility test used in mammography quality.

Personality, psychosocial and health-related predictors of quality of life in old age.

OBJECTIVES: Beyond its well-documented association with depressive symptoms across the lifespan, at an individual level, quality of life may be determined by multiple factors: psychosocial characteristics, current physical health and long-term personality traits. METHOD: Quality of life was assessed in two distinct community-based age groups (89 young adults aged 36.2 ± 6.3 and 92 older adults aged 70.4 ± 5.5 years), each group equally including adults with and without acute depressive symptoms. Regression models were applied to explore the association between quality of life assessed with the World Health Organization Quality of Life - Bref (WHOQOL-Bref) and depression severity, education, social support, physical illness, as well as personality dimensions as defined by the Five-Factor Model. RESULTS: In young age, higher quality of life was uniquely associated with lower severity of depressive symptoms. In contrast, in old age, higher quality of life was related to both lower levels of depressive mood and of physical illness. In this age group, a positive association was also found between quality of life and higher levels of Openness to experience and Agreeableness personality dimensions. CONCLUSION: Our data indicated that, in contrast to young cohorts, where acute depression is the main determinant of poor quality of life, physical illness and personality dimensions represent additional independent predictors of this variable in old age. This observation points to the need for concomitant consideration of physical and psychological determinants of quality of life in old age.

The Complementarity between segment disclosure and earnings quality, and its effect on cost of capital

We investigate the role of earnings quality in determining the levels of segment disclosure, and whether and how better quality earnings and segment disclosure influences cost of capital. Using a large US sample for the period 2001-2006, we find a positive relation between earnings quality and levels of segment disclosures. We also find that firms providing better quality segment information, contingent upon good earnings quality, enjoy lower cost of capital. We base our empirical tests on a self created index of segment disclosure. Our results contribute to a better understanding of (1) the incentives for providing segment disclosures, and (2) how accounting quality (quality of segment information and earnings quality) is related to the cost of capital.

Revisiting the size-R&D productivity relation: introducing the mediating role of decision-making style on the scale and quality of innovative output

We develop a mediation model in which firm size is proposed to affect the scale and quality of innovative output through the adoption of different decision styles during the R&D process. The aim of this study is to understand how the internal changes that firms undergo as they evolve from small to larger organizations affect R&D productivity. In so doing, we illuminate the underlying theoretical mechanism affecting two different dimensions of R&D productivity, namely the scale and quality of innovative output which have not received much attention in previous literature. Using longitudinal data of Spanish manufacturing firms we explore the validity of this mediation model. Our results show that as firms evolve in size, they increasingly emphasize analytical decision making, and consequently, large-sized firms aim for higher-quality innovations while small firms aim for a larger scale of innovative output.

Physiological differences between cycling and running: lessons from triathletes

The purpose of this review was to provide a synopsis of the literature concerning the physiological differences between cycling and running. By comparing physiological variables such as maximal oxygen consumption (V O(2max)), anaerobic threshold (AT), heart rate, economy or delta efficiency measured in cycling and running in triathletes, runners or cyclists, this review aims to identify the effects of exercise modality on the underlying mechanisms (ventilatory responses, blood flow, muscle oxidative capacity, peripheral innervation and neuromuscular fatigue) of adaptation. The majority of studies indicate that runners achieve a higher V O(2max) on treadmill whereas cyclists can achieve a V O(2max) value in cycle ergometry similar to that in treadmill running. Hence, V O(2max) is specific to the exercise modality. In addition, the muscles adapt specifically to a given exercise task over a period of time, resulting in an improvement in submaximal physiological variables such as the ventilatory threshold, in some cases without a change in V O(2max). However, this effect is probably larger in cycling than in running. At the same time, skill influencing motor unit recruitment patterns is an important influence on the anaerobic threshold in cycling. Furthermore, it is likely that there is more physiological training transfer from running to cycling than vice versa. In triathletes, there is generally no difference in V O(2max) measured in cycle ergometry and treadmill running. The data concerning the anaerobic threshold in cycling and running in triathletes are conflicting. This is likely to be due to a combination of actual training load and prior training history in each discipline. The mechanisms surrounding the differences in the AT together with V O(2max) in cycling and running are not largely understood but are probably due to the relative adaptation of cardiac output influencing V O(2max) and also the recruitment of muscle mass in combination with the oxidative capacity of this mass influencing the AT. Several other physiological differences between cycling and running are addressed: heart rate is different between the two activities both for maximal and submaximal intensities. The delta efficiency is higher in running. Ventilation is more impaired in cycling than in running. It has also been shown that pedalling cadence affects the metabolic responses during cycling but also during a subsequent running bout. However, the optimal cadence is still debated. Central fatigue and decrease in maximal strength are more important after prolonged exercise in running than in cycling.

Quality of care after acute coronary syndromes in a prospective cohort with reasons for non-prescription of recommended medications.

BACKGROUND: Adherence to guidelines is associated with improved outcomes of patients with acute coronary syndrome (ACS). Clinical registries developed to assess quality of care at discharge often do not collect the reasons for non-prescription for proven efficacious preventive medication in Continental Europe. In a prospective cohort of patients hospitalized for an ACS, we aimed at measuring the rate of recommended treatment at discharge, using pre-specified quality indicators recommended in cardiologic guidelines and including systematic collection of reasons for non-prescription for preventive medications. METHODS: In a prospective cohort with 1260 patients hospitalized for ACS, we measured the rate of recommended treatment at discharge in 4 academic centers in Switzerland. Performance measures for medication at discharge were pre-specified according to guidelines, systematically collected for all patients and included in a centralized database. RESULTS: Six hundred and eighty eight patients(54.6%) were discharged with a main diagnosis of STEMI, 491(39%) of NSTEMI and 81(6.4%) of unstable angina. Mean age was 64 years and 21.3% were women. 94.6% were prescribed angiotensin converting enzyme inhibitors/angiotensin II receptor blockers at discharge when only considering raw prescription rates, but increased to 99.5% when including reasons non-prescription. For statins, rates increased from 98% to 98.6% when including reasons for non-prescription and for beta-blockers, from 82% to 93%. For aspirin, rates further increased from 99.4% to 100% and from to 99.8% to 100% for P2Y12 inhibitors. CONCLUSIONS: We found a very high adherence to ACS guidelines for drug prescriptions at discharge when including reasons for non-prescription to drug therapy. For beta-blockers, prescription rates were suboptimal, even after taking into account reason for non-prescription. In an era of improving quality of care to achieve 100% prescription rates at discharge unless contra-indicated, pre-specification of reasons for non-prescription for cardiovascular preventive medication permits to identify remaining gaps in quality of care at discharge. TRIAL REGISTRATION: ClinicalTrials.gov NCT01000701.

Use of a renal-specific oral supplement by haemodialysis patients with low protein intake does not increase the need for phosphate binders and may prevent a decline in nutritional status and quality of life.

BACKGROUND: Protein-energy wasting is a frequent and debilitating condition in maintenance dialysis. We randomly tested if an energy-dense, phosphate-restricted, renal-specific oral supplement could maintain adequate nutritional intake and prevent malnutrition in maintenance haemodialysis patients with insufficient intake. METHODS: Eighty-six patients were assigned to a standard care (CTRL) group or were prescribed two 125-ml packs of Renilon 7.5(R) daily for 3 months (SUPP). Dietary intake, serum (S) albumin, prealbumin, protein nitrogen appearance (nPNA), C-reactive protein, subjective global assessment (SGA) and quality of life (QOL) were recorded at baseline and after 3 months. RESULTS: While intention to treat analysis (ITT) did not reveal strong statistically significant changes in dietary intake between groups, per protocol (PP) analysis showed that the SUPP group increased protein (P < 0.01) and energy (P < 0.01) intakes. In contrast, protein and energy intakes further deteriorated in the CTRL group (PP). Although there was no difference in serum albumin and prealbumin changes between groups, in the total population serum albumin and prealbumin changes were positively associated with the increment in protein intake (r = 0.29, P = 0.01 and r = 0.27, P = 0.02, respectively). The SUPP group did not increase phosphate intake, phosphataemia remained unaffected, and the use of phosphate binders remained stable or decreased. The SUPP group exhibited improved SGA and QOL (P < 0.05). CONCLUSION: This study shows that providing maintenance haemodialysis patients with insufficient intake with a renal-specific oral supplement may prevent deterioration in nutritional indices and QOL without increasing the need for phosphate binders.

La définition des interfaces pour améliorer la qualité: l'exemple de l'anorexie en hospitalisation somatique [Defining interfaces to improve quality of care: the example of anorexia nervosa in acute somatic hospitalisation]

Specialisation in medicine requires multidisciplinary approaches, and hence coordination in collaborations of the different partners involved. These integrated approaches, sometimes called "disease management", fit particularly well to chronic diseases. Our institution introduced an integrated approach for taking care of the acute somatic hospitalisation of patients suffering from anorexia nervosa. Interfaces with the different partners were defined, specifying tasks, rights, and duties of each person, care givers or patients. This initiative allows now to identify any deviation occurring in the process of care or hole in the care system, so that it can be corrected and recurrence prevented. This model will be extended to other complex and multidisciplinary care processes and other services in our institution.

Candidate quality in a Downsian Model with a continuous policy space

This paper characterizes a mixed strategy Nash equilibrium in a one-dimensional Downsian model of two-candidate elections with a continuous policy space, where candidates are office motivated and one candidate enjoys a non-policy advantage over the other candidate. We assume that voters have quadratic preferences over policies and that their ideal points are drawn from a uniform distribution over the unit interval. In our equilibrium the advantaged candidate chooses the expected median voter with probability one and the disadvantaged candidate uses a mixed strategy that is symmetric around it. We show that this equilibrium exists if the number of voters is large enough relative to the size of the advantage.

Individual versus standard quality of life assessment in a phase II clinical trial in mesothelioma patients: feasibility and responsiveness to clinical changes.

BACKGROUND: In patients with malignant pleural mesothelioma undergoing a multimodality therapy, treatment toxicity may outweigh the benefit of progression-free survival. The subjective experience across different treatment phases is an important clinical outcome. This study compares a standard with an individual quality of life (QoL) measure used in a multi-center phase II trial. PATIENTS AND METHODS: Sixty-one patients with stage I-III technically operable pleural mesothelioma were treated with preoperative chemotherapy, followed by pleuropneumonectomy and subsequent radiotherapy. QoL was assessed at baseline, at day 1 of cycle 3, and 1, 3 and 6 months post-surgery by using the Rotterdam Symptom Checklist (RSCL) and the Schedule for the Evaluation of Quality of Life-Direct Weighting (SEIQoL-DW), a measure that is based on five individually nominated and weighted QoL-domains. RESULTS: Completion rates were 98% (RSCL) and 92% (SEIQoL) at baseline and 98%/89% at cycle 3, respectively. Of the operated patients (N=45) RSCL and SEIQoL were available from 86%/72%, 93%/74%, and 94%/76% at months 1, 3, and 6 post-surgery. Average assessment time for the SEIQoL was 24min compared to 8min needed for the RSCL. Median changes from baseline indicate that both RSCL QoL overall score and SEIQoL index remained stable during chemotherapy with a clinically significant deterioration (change>or=8 points) 1 month after surgery (median change of -66 and -14 for RSCL and SEIQoL, respectively). RSCL QoL overall scores improved thereafter, but remained beneath baseline level until 6 months after surgery. SEIQoL scores improved to baseline-level at month 3 after surgery, but worsened again at month 6. RSCL QoL overall score and SEIQoL index were moderately correlated at baseline (r=.30; p<or=.05) and at 6-month follow-up (r=.42; p<or=.05) but not at the other time points. CONCLUSION: The SEIQoL assessment seems to be feasible within a phase II clinical trial, but may require more effort from staff. More distinctive QoL changes in accordance with clinical changes were measured with the RSCL. Our findings suggest that the two measures are not interchangeable: the RSCL is to favor when mainly information related to the course of disease- and treatment is of interest.

Quality assurance in the EORTC 22033-26033/CE5 phase III randomized trial for low grade glioma: the digital individual case review.

INTRODUCTION: The phase III EORTC 22033-26033/NCIC CE5 intergroup trial compares 50.4 Gy radiotherapy with up-front temozolomide in previously untreated low-grade glioma. We describe the digital EORTC individual case review (ICR) performed to evaluate protocol radiotherapy (RT) compliance. METHODS: Fifty-eight institutions were asked to submit 1-2 randomly selected cases. Digital ICR datasets were uploaded to the EORTC server and accessed by three central reviewers. Twenty-seven parameters were analysed including volume delineation, treatment planning, organ at risk (OAR) dosimetry and verification. Consensus reviews were collated and summary statistics calculated. RESULTS: Fifty-seven of seventy-two requested datasets from forty-eight institutions were technically usable. 31/57 received a major deviation for at least one section. Relocation accuracy was according to protocol in 45. Just over 30% had acceptable target volumes. OAR contours were missing in an average of 25% of cases. Up to one-third of those present were incorrectly drawn while dosimetry was largely protocol compliant. Beam energy was acceptable in 97% and 48 patients had per protocol beam arrangements. CONCLUSIONS: Digital RT plan submission and review within the EORTC 22033-26033 ICR provide a solid foundation for future quality assurance procedures. Strict evaluation resulted in overall grades of minor and major deviation for 37% and 32%, respectively.