Design and application of a structured phantom for detection performance comparison between breast tomosynthesis and digital mammography.

This paper introduces and applies a structured phantom with inserted target objects for the comparison of detection performance of digital breast tomosynthesis (DBT) against 2D full field digital mammography (FFDM). The phantom consists of a 48 mm thick breast-shaped polymethyl methacrylate (PMMA) container filled with water and PMMA spheres of different diameters. Three-dimensionally (3D) printed spiculated masses (diameter range: 3.8-9.7 mm) and non-spiculated masses (1.6-6.2 mm) along with microcalcifications (90-250 µm) were inserted as targets. Reproducibility of the phantom application was studied on a single system using 30 acquisitions. Next, the phantom was evaluated on five different combined FFDM & DBT systems and target detection was compared for FFDM and DBT modes. Ten phantom images in both FFDM and DBT modes were acquired on these 5 systems using automatic exposure control. Five readers evaluated target detectability. Images were read with the four-alternative forced-choice (4-AFC) paradigm, with always one segment including a target and 3 normal background segments. The percentage of correct responses (PC) was assessed based on 10 trials of each reader for each object type, size and imaging modality. Additionally, detection threshold diameters at 62.5 PC were assessed via non-linear regression fitting of the psychometric curve. The reproducibility study showed no significant differences in PC values. Evaluation of target detection in FFDM showed that microcalcification detection thresholds ranged between 110 and 118 µm and were similar compared to the detection in DBT (range of 106-158 µm). In DBT, detection of both mass types increased significantly (p = 0.0001 and p = 0.0002 for non-spiculated and spiculated masses respectively) compared to FFDM, achieving almost 100% detection for all spiculated mass diameters. In conclusion, a structured phantom with inserted targets was able to show evidence for detectability differences between FFDM and DBT modes for five commercial systems. This phantom has potential for application in task-based assessment at acceptance and commissioning testing of DBT systems.

Bottom-up implementation of disease-management programmes: results of a multisite comparison.

OBJECTIVES: To evaluate the implementation of three regional disease-management programmes on chronic obstructive pulmonary disease (COPD) based on bottlenecks experienced in professional practice. METHODS: The authors performed a multisite comparison of three Dutch regional disease-management programmes combining patient-related, professional-directed and organisational interventions. Process (Assessing Chronic Illness Care survey) and outcome (disease specific quality of life (clinical COPD questionnaire (CCQ); chronic respiratory questionnaire (CRQ)), Medical Research Council dyspnoea and patients' experiences) data were collected for 370 COPD patients and their care providers. RESULTS: Bottlenecks in region A were mostly related to patient involvement, in region B to organisational issues and in region C to both. Selected interventions related to identified bottlenecks were implemented in all programmes, except for patient-related interventions in programme A. Within programmes, significant improvements were found on dyspnoea and patients' experiences with practice nurses. Outcomes on quality of life differed between programmes: programme A did not show any significant improvements; programme B did show any significant improvements on CCQ total (p<0.001), functional (p=0.011) and symptom (p<0.001), CRQ fatigue (p<0.001) and emotional scales (p<0.001); in programme C, CCQ symptom (p<0.001) improved significantly, whereas CCQ mental score (p<0.001) deteriorated significantly. Regression analyses showed that programmes with better implementation of selected interventions resulted in relatively larger improvements in quality of life (CCQ). CONCLUSIONS: Bottom-up implementation of COPD disease-management programmes is a feasible approach, which in multiple settings leads to significant improvements in outcomes of care. Programmes with a better fit between implemented interventions and bottlenecks showed more positive changes in outcomes.

Identifying potentially cost effective chronic care programs for people with COPD.

OBJECTIVE: To review published evidence regarding the cost effectiveness of multi-component COPD programs and to illustrate how potentially cost effective programs can be identified. METHODS: Systematic search of Medline and Cochrane databases for evaluations of multi-component disease management or chronic care programs for adults with COPD, describing process, intermediate, and end results of care. Data were independently extracted by two reviewers and descriptively summarized. RESULTS: Twenty articles describing 17 unique COPD programs were included. There is little evidence for significant improvements in process and intermediate outcomes, except for increased provision of patient self-management education and improved disease-specific knowledge. Overall, the COPD programs generate end results equivalent to usual care, but programs containing >or=3 components show lower relative risks for hospitalization. There is limited scope for programs to break-even or save money. CONCLUSION: Identifying cost effective multi-component COPD programs remains a challenge due to scarce methodologically sound studies that demonstrate significant improvements on process, intermediate and end results of care. Estimations of potential cost effectiveness of specific programs illustrated in this paper can, in the absence of 'perfect data', support timely decision-making regarding these programs. Nevertheless, well-designed health economic studies are needed to decrease the current decision uncertainty.

A large-scale multicentre study of patient skin doses in interventional cardiology: dose-area product action levels and dose reference levels.

For 318 patients in 8 different Belgian hospitals, the entire skin-dose distribution was mapped using a grid of 70 thermoluminescence dosimeters per patient, allowing an accurate determination of the maximum skin dose (MSD). Dose-area product (DAP) values, exposure parameters and geometry, together with procedure, patient and cardiologist characteristics, were also registered. Procedures were divided into two groups: diagnostic procedures (coronary angiography) and therapeutic procedures (dilatation, stent, combined procedures (e.g. coronary angiography + dilatation + stent)). The mean value of the MSD was 0.310 Gy for diagnostic and 0.699 Gy for therapeutic procedures. The most critical projection for receiving the MSD is the LAO90 (left anterior oblique) geometry. In 3% of cases, the MSD exceeded the 2 Gy dose threshold for deterministic effects. Action levels in terms of DAP values as the basis for a strategy for follow-up of patients for deterministic radiation skin effects were derived from measured MSD and cumulative DAP values. Two DAP action levels are proposed. A first DAP action level of 125 Gy cm(2) corresponding to the dose threshold of 2 Gy would imply an optional radiopathological follow-up depending on the cardiologist's decision. A second DAP action level of 250 Gy cm(2) corresponding to the 3 Gy skin dose would imply a systematic follow-up. Dose reference levels - 71.3 Gy cm(2) for diagnostic and 106.0 Gy cm(2) for therapeutic procedures - were derived from the 75 percentile of the DAP distributions. As a conclusion, we propose that total DAP is registered in patient's record file, as it can serve to improve the follow-up of patients for radiation-induced skin injuries.

Modelling antecedents of blood donation motivation among non-donors of varying age and education.

Understanding blood donation motivation among non-donors is prerequisite to effective recruitment. Two studies explored the psychological antecedents of blood donation motivation and the generalisability of a model of donation motivation across groups differing in age and educational level. An older well-educated population and a younger less well-educated population were sampled. The studies assessed the role of altruism, fear of blood/needles and donation-specific cognitions including attitudes and normative beliefs derived from an extended theory of planned behaviour (TPB). Across both samples, results showed that affective attitude, subjective norm, descriptive norm, and moral norm were the most important correlates of blood donation intentions. Self-efficacy was more important among the younger less well-educated group. Altruism was related to donation motivation but only indirectly through moral norm. Similarly, fear of blood/needles only had an indirect effect on motivation through affective attitude and self-efficacy. Additional analyses with the combined data set found no age or education moderation effects, suggesting that this core model of donation-specific cognitions can be used to inform future practical interventions recruiting new blood donors in the general population.

A model to evaluate quality and effectiveness of disease management.

Disease management has emerged as a new strategy to enhance quality of care for patients suffering from chronic conditions, and to control healthcare costs. So far, however, the effects of this strategy remain unclear. Although current models define the concept of disease management, they do not provide a systematic development or an explanatory theory of how disease management affects the outcomes of care. The objective of this paper is to present a framework for valid evaluation of disease-management initiatives. The evaluation model is built on two pillars of disease management: patient-related and professional-directed interventions. The effectiveness of these interventions is thought to be affected by the organisational design of the healthcare system. Disease management requires a multifaceted approach; hence disease-management programme evaluations should focus on the effects of multiple interventions, namely patient-related, professional-directed and organisational interventions. The framework has been built upon the conceptualisation of these disease-management interventions. Analysis of the underlying mechanisms of these interventions revealed that learning and behavioural theories support the core assumptions of disease management. The evaluation model can be used to identify the components of disease-management programmes and the mechanisms behind them, making valid comparison feasible. In addition, this model links the programme interventions to indicators that can be used to evaluate the disease-management programme. Consistent use of this framework will enable comparisons among disease-management programmes and outcomes in evaluation research.

Identifying blood donors willing to help with recruitment.

BACKGROUND AND OBJECTIVES: Social influence shapes behaviour and donors are ambassadors for blood banks. Donors are role models for family and friends and, therefore, so may be able to help with donor recruitment. MATERIALS AND METHODS: A questionnaire was used to assess donors' willingness to engage in donor recruitment. Measures included willingness to recruit new donors and antecedents of recruitment motivation based on the theory of planned behaviour (TPB). RESULTS: More than half of our participants were willing to try to recruit friends and family (57%). Self-efficacy was the most important correlate of intention to recruit as were cognitive attitude and experience with the blood bank. The findings suggest that the TPB provides a good basis for understanding cognitive antecedents of donors' willingness to recruit other donors. CONCLUSION: Results suggest that using existing donors to recruit new donors could be an efficient and cost-effective way to recruit additional donors. This approach warrants further investigation.

Designing patient-related interventions in COPD care: empirical test of a theoretical model.

OBJECTIVES: The aim of this exploratory study was to test the applicability of a theoretical model to develop patient-related interventions. In this model knowledge, psychosocial mediators, self-efficacy and behaviour are determinants of patient-related interventions. METHODS: The model was tested on 278 patients with mild or moderate chronic obstructive pulmonary disease (COPD), recruited in a primary care setting. Hierarchical regression analyses were applied using data from self-reported questionnaires and clinical data from an electronic data registry. RESULTS: Knowledge, psychosocial mediators, self-efficacy and behaviour proved to be, to a moderate degree, predictors of outcomes in COPD care. Moreover, physical activity appeared to be a significant predictor for all clinical and functional outcomes. CONCLUSION: Theoretically expected associations of patient-related interventions are existent in patients with mild or moderate COPD. The application of theoretical models in designing patient-directed interventions in COPD care is therefore feasible. PRACTICE IMPLICATIONS: More attention should be paid to the patterns of physical activity in patients with mild to moderate COPD. The results of this study are also useful in the development of patient-related interventions. Future interventions should be designed along the lines of theory on behaviour change, such as social cognitive theory.

Results of a European dose survey for mammography.

For the dose study, a semi-automated method of data collection is used in this study. The participating centres were asked to fill out a spreadsheet with all necessary data and return it. For direct digital (DR) systems, the relevant data available in the DICOM header were used. All data is automatically added to a database and processed. The data were used to calculate the mean glandular dose for every image and for different thicknesses of polymethyl methacrylate phantoms using available conversion factors. Second-degree polynomials were fitted to the patient dose data and a reference dose curve was constructed for a range of thicknesses instead of a dose reference level at a single point. The dose reference curve rises from 1.57 mGy for a thickness of 30 mm to 2.50 mGy for 55 mm and 3.83 mGy for 75 mm. The results show centres that exceed this curve lie only in the lower or higher range of thicknesses and would remain undetected using a dose reference value in a single point. This gives better information to radiographers on where there is room for improvement of the dose levels in their system.

Non-algorithmic access to calendar information in a calendar calculator with autism.

The possible use of a calendar algorithm was assessed in DBC, an autistic "savant" of normal measured intelligence. Testing of all the dates in a year revealed a random distribution of errors. Re-testing DBC on the same dates one year later shows that his errors were not stable across time. Finally, DBC was able to answer "reversed" questions that cannot be solved by a classical algorithm. These findings favor a non-algorithmic retrieval of calendar information. It is proposed that multidirectional, non-hierarchical retrieval of information, and solving problems in a non-algorithmic way, are involved in savant performances. The possible role of a functional rededication of low-level perceptual systems to the processing of symbolic information in savants is discussed.

Why don't young people volunteer to give blood? An investigation of the correlates of donation intentions among young nondonors.

BACKGROUND: In the past decade, the number of blood donors has steadily declined in the Netherlands, and young adults are underrepresented among registered donors. An understanding of the correlates of donation intentions among nondonors could facilitate targeting psychological prerequisites of donation decisions in recruitment campaigns. STUDY DESIGN AND METHODS. A cross-sectional study with self-administered questionnaires based on an extension of the Theory of Planned Behavior (TPB; a social cognition model to study the determinants of volitional behavior) was conducted to assess potential cognitive determinants of willingness to donate blood in a student sample. A response rate of 50.5 percent yielded a sample of 311. RESULTS: Just over 7 percent of participants were registered blood donors but most (61.7%) had never seriously considered becoming donors. Self-efficacy (confidence in performing the behavior), attitude (the overall evaluation of the behavior), and personal moral norm (the perceived personal responsibility to perform the behavior) regarding blood donation were the most important correlates of the intention to become a blood donor. In total, 43 percent of the variance in the intentions toward blood donation could be explained by a TPB-based model. CONCLUSION: Among students, determinants of the intention to become a blood donor include self-efficacy, attitude, personal moral norm regarding blood donation, and subjective norm (perceived social support). Future research could establish whether campaigns targeting these psychological prerequisites would be more effective than current strategies.

Thiamine-responsive megaloblastic anemia syndrome (TRMA) with cone-rod dystrophy.

Thiamine-responsive megaloblastic anemia (TRMA) is an autosomal recessive disease in which the active thiamine uptake into cells is disturbed. The molecular basis underlying the disorder has been related to mutations in the gene SLC19A2 on chromosome 1q23.3 that encodes a functional thiamine transporter. The protein is predicted to have 12 transmembrane domains. TRMA is characterized by sensorineural deafness, diabetes mellitus, megaloblastic anemia, and cardiomyopathy. Optic nerve atrophy and retinal dystrophy have been reported in a small number of patients. We report a 15-year-old girl with TRMA and cone-rod dystrophy and confirm that retinal dystrophy may form part of the syndrome. Differential diagnosis of syndromes with deafness, diabetes mellitus, and optic nerve atrophy or retinal dystrophy are discussed. The authors suggest that ERG be performed in all patients with TRMA.