Development and validation of a psychometric scale for assessing PA chest image quality: a pilot study

Purpose - To develop and validate a psychometric scale for assessing image quality perception for chest X-ray images. Methods - Bandura's theory was used to guide scale development. A review of the literature was undertaken to identify items/factors which could be used to evaluate image quality using a perceptual approach. A draft scale was then created (22 items) and presented to a focus group (student and qualified radiographers). Within the focus group the draft scale was discussed and modified. A series of seven postero-anterior chest images were generated using a phantom with a range of image qualities. Image quality perception was confirmed for the seven images using signal-to-noise ratio (SNR 17.2–36.5). Participants (student and qualified radiographers and radiology trainees) were then invited to independently score each of the seven images using the draft image quality perception scale. Cronbach alpha was used to test interval reliability. Results - Fifty three participants used the scale to grade image quality perception on each of the seven images. Aggregated mean scale score increased with increasing SNR from 42.1 to 87.7 (r = 0.98, P < 0.001). For each of the 22 individual scale items there was clear differentiation of low, mid and high quality images. A Cronbach alpha coefficient of >0.7 was obtained across each of the seven images. Conclusion - This study represents the first development of a chest image quality perception scale based on Bandura's theory. There was excellent correlation between the image quality perception scores derived using the scale and the SNR. Further research will involve a more detailed item and factor analysis.

Aspectos de fiabilidad y validez de los dilemas implicativos

Los dilemas implicativos, un tipo de conflicto cognitivo que puede detectarse mediante la Técnica de Rejilla (TR), aparecen cuando una característica personal que se desea cambiar (en términos de la TR, un constructo discrepante ) se asocia con otra característica que se desea conservar (constructo congruente ). El cambio deseado en el constructor discrepante se ve bloqueado porque según la visión de la persona conllevaría el riesgo de un cambio no deseado en el constructo congruente. Los dilemas implicativos proporcionan una posible explicación de por qué muchas personas desean cambiar algo de si mismas (p. ej., salir a la calle o ser más sociables ) y sin embargo no lo hacen. Algunos estudios han encontrado que diversas poblaciones con problemas psíquicos (p.e. depresión, bulimia nerviosa) o físicos (fibromialgia) presentan más frecuentemente dilemas implicativos en sus rejillas que personas sin estos trastornos. Otras investigaciones vinculan la mejora en pacientes de psicoterapia a la resolución de estos dilemas durante la misma. El presente proyecto se dedica a investigar diferentes aspectos de fiabilidad y validez de los dilemas implicativos mediante cuatro tipos de estudios: a) relación entre dilemas implicativos y cuestionarios de sintomatología en muestras tanto clínicas como no clínicas (validez convergente); b)presencia diferencial de dilemas implicativos en muestras clínicas en comparación con controles no clínicos (validez de critero); c)grado en que las personas, al ser confrontadas con sus propios dilemas, los reconocen como una información válida y relevante para sus vidas (validez subjetiva); y d)determinar la estabilidad temporal (fiabilidad test-retest) de un conjunto de índices derivados de la TR, incluyendo los dilemas implicativos. Para ello se han planificado ocho estudios, de los cuales una ya está publicado y los demás están en diferentes etapas de realización. En el apartado 2 se incluye un resumen de cada uno de ellos.

Continuous monitoring of liver oxygenation with near infrared spectroscopy during naso-gastric tube feeding in neonates.

Near infrared spectroscopy (NIRS) is a non-invasive method of estimating the haemoglobin concentration changes in certain tissues. It is frequently used to monitor oxygenation of the brain in neonates. At present it is not clear whether near infrared spectroscopy of other organs (e.g. the liver as a corresponding site in the splanchnic region, which reacts very sensitively to haemodynamic instability) provides reliable values on their tissue oxygenation. The aim of the study was to test near infrared spectroscopy by measuring known physiologic changes in tissue oxygenation of the liver in newborn infants during and after feeding via a naso-gastric tube. The test-retest variability of such measurements was also determined. On 28 occasions in 25 infants we measured the tissue oxygenation index (TOI) of the liver and the brain continuously before, during and 30 minutes after feeding via a gastric tube. Simultaneously we measured arterial oxygen saturation (SaO2), heart rate (HR) and mean arterial blood pressure (MAP). In 10 other newborn infants we performed a test-retest analysis of the liver tissue oxygenation index to estimate the variability in repeated intra-individual measurements. The tissue oxygenation index of the liver increased significantly from 56.7 +/- 7.5% before to 60.3 +/- 5.6% after feeding (p < 0.005), and remained unchanged for the next 30 minutes. The tissue oxygenation index of the brain (62.1 +/- 9.7%), SaO2 (94.4 +/- 7.1%), heart rate (145 +/- 17.3 min-1) and mean arterial blood pressure (52.8 +/- 10.2 mm Hg) did not change significantly. The test-retest variability for intra-individual measurements was 2.7 +/- 2.1%. After bolus feeding the tissue oxygenation index of the liver increased as expected. This indicates that near infrared spectroscopy is suitable for monitoring changes in tissue oxygenation of the liver in newborn infants.

Qualité des soins ambulatoires : opinion des patients infectés par le VIH

Ce travail décrit une étude, qui a visé à évaluer la performance d'un questionnaire de satisfaction en développement, destiné à mesurer l'opinion de patients infectés par le VIH suivis ambulatoirement. 1. Problématique. 1.1. La qualité des soins, une définition. 1.2. L'opinion des patients : comment la mesurer ? Le questionnaire, les questionnaires existants, le focus groups, description de la technique. 2. Patients et méthodes. 2.1. Critères d'inclusion et d'exclusion. 2.2. Les envois et les rappels. 2.3. Stabilité test-retest. 2.4. Le recrutement. 3. Résultats. 3.1. Acceptabilité du questionnaire : participation. 3.2. Représentativité de l'échantillon. 3.3. Scores par dimension. 3. 4. Evaluation de la validité du questionnaire, convergence des items par dimension et cohérence interne. 3.5. Les questions issues du questionnaire SF-36. 4. Discussion. 4.1. Coping et méthodes alternatives. 4.2. Impact sur les service d'une enquête sur la qualité des soins. 5.1. Le questionnaire de satisfaction élaboré. 5.2. Les différents questionnaires des Hospices : patients hospitalisés et ambulatoires. 5.3. Formulaire d'information de l'enquête par questionnaire. 5.4. Formulaire de consentement à l'enquête. 5.5. Lettre d'accompagnement du questionnaire. 5.6. Profil socio-démographique et résultats complets par item.

Stimulation-induced increases of astrocytic oxidative metabolism in rats and humans investigated with 1-11C-acetate

The purpose of this study was to investigate astrocytic oxidative metabolism using 1-(11)C-acetate. 1-(11)C-acetate kinetics were evaluated in the rat somatosensory cortex using a beta-scintillator during different manipulations (test-retest, infraorbital nerve stimulation, and administration of acetazolamide or dichloroacetate). In humans a visual activation paradigm was used and kinetics were measured with positron emission tomography. Data were analyzed using a one-tissue compartment model. The following features supported the hypothesis that washout of radiolabel (k(2)) is because of (11)C-CO(2) and therefore related to oxygen consumption (CMRO(2)): (1) the onset of (11)C washout was delayed; (2)k(2) was not affected by acetazolamide-induced blood flow increase; (3)k(2) demonstrated a significant increase during stimulation in rats (from 0.014+/-0.007 to 0.027+/-0.006 per minute) and humans (from 0.016+/-0.010 to 0.026+/-0.006 per minute); and (4) dichloroacetate led to a substantial decrease of k(2). In the test-retest experiments K(1) and k(2) were very stable. In summary, 1-(11)C-acetate seems a promising tracer to investigate astrocytic oxidative metabolism in vivo. If the washout rate indeed represents the production of (11)C-CO(2), then its increase during stimulation would point to a substantially higher astrocytic oxidative metabolism during brain activation. However, the quantitative relationship between k(2) and CMRO(2) needs to be determined in future experiments.

Eating habits of preschool children with high migrant status in Switzerland according to a new food frequency questionnaire.

Assessment of eating habits in young children from multicultural backgrounds has seldom been conducted. Our objectives were to study the reproducibility and the results of a food frequency questionnaire (FFQ) developed to assess changes in eating habits of preschool children with a high migrant population, in the context of a multidisciplinary multilevel lifestyle intervention. Three kindergarten classes (53% from migrant backgrounds) in French-speaking Switzerland were randomly selected and included 16 girls and 28 boys (mean age +/- SD, 5.4 +/- 0.7 years). The FFQ was filled out twice within a 4-week interval by the parents. Spearman rank correlations between the first and the second FFQ for the 39 items of the food questions were as follows: low (r < 0.50) for 8 (7 P < .05 and 1 nonsignificant), moderate (0.50 <or= r < 0.70) for 22 (all P < .01), and high (r >or= 0.70) for 9 (all P < .01). In addition, 28 of 39 intraclass correlation coefficients were high (>0.50, all P < .01). Eighty-six percent of the children ate breakfast at home daily, but only 67% had lunch at home. The percentages of children eating at least once a week in front of the TV were as follows: 50% for breakfast, 33% for lunch, 38% for dinner, and 48% for snacks. Forty percent of children asked their parents to buy food previously seen in advertisements and ate fast food between once a week and once a month. Children generally consumed foods with a high-energy content. The FFQ yielded good test-retest reproducibility for most items of the food questions and gave relevant findings about the eating habits of preschool children in areas with a high migrant population.

Clinical Learning Environment and Supervision. Development and Validation of the CLES Evaluation Scale

The purpose of the study is: (1) to describe how nursing students' experienced their clinical learning environment and the supervision given by staff nurses working in hospital settings; and (2) to develop and test an evaluation scale of Clinical Learning Environment and Supervision (CLES). The study has been carried out in different phases. The pilot study (n=163) explored the association between the characteristics of a ward and its evaluation as a learning environment by students. The second version of research instrument (which was developed by the results of this pilot study) were tested by an expert panel (n=9 nurse teachers) and test-retest group formed by student nurses (n=38). After this evaluative phase, the CLES was formed as the basic research instrument for this study and it was tested with the Finnish main sample (n=416). In this phase, a concurrent validity instrument (Dunn & Burnett 1995) was used to confirm the validation process of CLES. The international comparative study was made by comparing the Finnish main sample with a British sample (n=142). The international comparative study was necessary for two reasons. In the instrument developing process, there is a need to test the new instrument in some other nursing culture. Other reason for comparative international study is the reflecting the impact of open employment markets in the European Union (EU) on the need to evaluate and to integrate EU health care educational systems. The results showed that the individualised supervision system is the most used supervision model and the supervisory relationship with personal mentor is the most meaningful single element of supervision evaluated by nursing students. The ward atmosphere and the management style of ward manager are the most important environmental factors of the clinical ward. The study integrates two theoretical elements - learning environment and supervision - in developing a preliminary theoretical model. The comparative international study showed that, Finnish students were more satisfied and evaluated their clinical placements and supervision with higher scores than students in the United Kingdom (UK). The difference between groups was statistical highly significant (p= 0.000). In the UK, clinical placements were longer but students met their nurse teachers less frequently than students in Finland. Arrangements for supervision were similar. This research process has produced the evaluation scale (CLES), which can be used in research and quality assessments of clinical learning environment and supervision in Finland and in the UK. CLES consists of 27 items and it is sub-divided into five sub-dimensions. Cronbach's alpha coefficient varied from high 0.94 to marginal 0.73. CLES is a compact evaluation scale and user-friendliness makes it suitable for continuing evaluation.

Desarrollo y evaluación psicométrica de una forma abreviada de la escala de posicionamiento ante el diagnóstico enfermero

El Position on Nursing Diagnosis (PND) es una escala que utiliza la técnica del diferencial semántico para medir las actitudes hacia el concepto diagnóstico enfermero. El estudio objetivó desarrollar una forma abreviada de la versión española de esta escala, evaluar sus propiedades psicométricas y eficiencia. Se utilizó un doble enfoque empírico-teórico para obtener una forma reducida del PND, el PND-7-SV, que fuera equivalente a la original. Mediante un diseño transversal a través de encuesta, se evaluó la fiabilidad (consistencia interna y fiabilidad test-retest), validez de constructo (análisis factorial exploratorio, técnica de grupos conocidos y validez discriminante) y de criterio (validez concurrente), sensibilidad al cambio y eficiencia del PND-7-SV en una muestra de 476 estudiantes de enfermería españoles. Los resultados avalaron la utilidad del PND-7-SV para medir las actitudes hacia el diagnóstico enfermero de manera equivalente a la forma completa de la escala y en un tiempo más reducido.

Dielectric constant obtained from TDR and volumetric moisture of soils in southern Brazil

Soil moisture is the property which most greatly influences the soil dielectric constant, which is also influenced by soil mineralogy. The aim of this study was to determine mathematical models for soil moisture and the dielectric constant (Ka) for a Hapludalf, two clayey Hapludox and a very clayey Hapludox and test the reliability of universal models, such as those proposed by Topp and Ledieu and their co-workers in the 80's, and specific models to estimate soil moisture with a TDR. Soil samples were collected from the 0 to 0.30 m layer, sieved through a mesh of 0.002 m diameter and packed in PVC cylinders with a 0.1 m diameter and 0.3 m height. Seven samples of each soil class were saturated by capillarity and a probe composed of two rods was inserted in each one of them. Moisture readings began with the saturated soil and concluded when the soil was near permanent wilting point. In each step, the samples were weighed on a precision scale to calculate volumetric moisture. Linear and polynomial models were adjusted for each soil class and for all soils together between soil moisture and the dielectric constant. Accuracy of the models was evaluated by the coefficient of determination, the standard error of estimate and the 1:1 line. The models proposed by Topp and Ledieu and their co-workers were not adequate for estimating the moisture in the soil classes studied. The adjusted linear and polynomial models for the entire set of data of the four soil classes did not have sufficient accuracy for estimating soil moisture. The greater the soil clay and Fe oxide content, the greater the dielectric constant of the medium for a given volumetric moisture. The specific models, θ = 0.40283 - 0.04231 Ka + 0.00194 Ka² - 0.000022 Ka³ (Hapludox) θ = 0.01971 + 0.02902 Ka - 0.00086 Ka² + 0.000012 Ka³ (Hapludox -PF), θ = 0.01692 - 0.00507 Ka (Hapludalf) and θ = 0.08471 + 0.01145 Ka (Hapludox-CA), show greater accuracy and reliability for estimating soil moisture in the soil classes studied.

Development of a Sensitive Resource Use Questionnaire

Alcoholism is a chronic disease and the evaluation of its burden usually focuses on long-term co-morbidity and mortality. Clinical Trials evaluating new interventions for alcohol-dependent patients rarely last more than 12 to 24 months. OBJECTIVES: Develop a questionnaire capable of capturing principal resource use yet sensitive enough to show short-term economic benefit of drugs developed to reduce consump¬tion in alcohol-dependent patients. METHODS: Comprehensive Medline literature search using keywords: Alcohol-related-disorders, economics, cost of illness. Further, experts panel discussions provided additional data. RESULTS: Two key cost drivers, hospitalisation and sick leaves were identified by the literature review. Expert findings related to costs of social consequences were incorporated. These three important resources were included in the questionnaire in addition to standard medical resource use consumption input. Finally, the following items were included: consultation visits, hospitalisations, sick leaves and working situation, living situation, social environ¬ment, accidents, arrests and domestic violence. The recall period is 3 months. DISCUSSION: A great deal of information is collected in this questionnaire in order to capture all relevant resources. Tests to validate the questionnaire in a real-life setting will be conducted (face validity, concurrent validity, and test-retest) in a cohort of dependent patients initiated at Lausanne University hospital ( Switzerland). Items not sensitive enough to capture short-term costs and consequences will be removed. Translation into other major languages and adaptation to different settings after cultural validation is planned. CONCLUSIONS: Publication of this tool should facilitate additional knowledge about resource utilisation at the patient level and enable evaluation of short-term economic impact of pharmacological and non-pharmacological interventions.

Human finger somatotopy in areas 3b, 1, and 2: A 7T fMRI study using a natural stimulus.

To study the properties of human primary somatosensory (S1) cortex as well as its role in cognitive and social processes, it is necessary to noninvasively localize the cortical representations of the body. Being arguably the most relevant body parts for tactile exploration, cortical representations of fingers are of particular interest. The aim of the present study was to investigate the cortical representation of individual fingers (D1-D5), using human touch as a stimulus. Utilizing the high BOLD sensitivity and spatial resolution at 7T, we found that each finger is represented within three subregions of S1 in the postcentral gyrus. Within each of these three areas, the fingers are sequentially organized (from D1 to D5) in a somatotopic manner. Therefore, these finger representations likely reflect distinct activations of BAs 3b, 1, and 2, similar to those described in electrophysiological work in non-human primates. Quantitative analysis of the local BOLD responses revealed that within BA3b, each finger representation is specific to its own stimulation without any cross-finger responsiveness. This finger response selectivity was less prominent in BA 1 and in BA 2. A test-retest procedure highlighted the reproducibility of the results and the robustness of the method for BA 3b. Finally, the representation of the thumb was enlarged compared to the other fingers within BAs 1 and 2. These findings extend previous human electrophysiological and neuroimaging data but also reveal differences in the functional organization of S1 in human and nonhuman primates. Hum Brain Mapp 35:213-226, 2014. © 2012 Wiley Periodicals, Inc.

Validation of the 34-item Supportive Care Needs Survey and 8-item Breast module French versions (SCNS-SF34-Fr and SCNS-BR8-Fr) in breast cancer patients.

This study aimed to assess the psychometric robustness of the French version of the Supportive Care Needs Survey and breast cancer (BC) module (SCNS-SF34-Fr and SCNS-BR8-Fr). Breast cancer patients were recruited in two hospitals (in Paris, France and Lausanne, Switzerland) either in ambulatory chemotherapy or radiotherapy, or surgery services. They were invited to complete the SCNS-SF34-Fr and SCNS-BR8-Fr as well as quality of life and patient satisfaction questionnaires. Three hundred and eighty-four (73% response rate) BC patients returned completed questionnaires. A five-factor model was confirmed for the SCNS-SF34-Fr with adequate goodness-of-fit indexes, although some items evidenced content redundancy, and a one-factor was identified for the SCNS-BR8-Fr. Internal consistency and test-retest estimates were satisfactory for most scales. The SCNS-SF34-Fr and SCNS-BR8-Fr scales demonstrated conceptual differences with the quality of life and satisfaction with care scales, highlighting the specific relevance of this assessment. Different levels of needs could be differentiated between groups of BC patients in terms of age and level of education (P < 0.001). The SCNS-SF34-Fr and SCNS-BR8-Fr present adequate psychometric properties despite some redundant items. These questionnaires allow for the crucial endeavour to design appropriate care services according to BC patients' characteristics.

Stimulus-response curve of human motor nerves: multicenter assessment of various indexes.

The value of various indexes to characterize the stimulus-response curve of human motor nerves was assessed in 40 healthy subjects recruited from four European centers of investigation (Créteil, Lausanne, Liège, Marseille). Stimulus-response curves were established by stimulating the right median and ulnar motor nerves at the wrist, with stimulus durations of 0.05 and 0.5 ms. The following parameters were studied: the threshold intensity of stimulation to obtain 10% (I 10), 50% (I 50), and 90% (I 90) of the maximal compound muscle action potential, the ratios I 10/I 50, I 90/I 50, (I 90 - I 10)/I 10, (I 90-I 50)/I 50, and (I 50 - I 10)/I 10, and the slopes of the stimulus-response curves with or without normalization to I 50. For each parameter, within-center variability and reproducibility (in a test-retest study) were assessed and between-center comparisons were made. For most of the parameters, the results varied significantly within and between the centers. Within the centers, only the ratios I 10/I 50 and I 90/I 50 were found constant and reproducible. Between the centers, the absolute intensity thresholds (I 10, I 50, I 90) and the ratio I 90/I 50 did not show significant differences at stimulus duration of 0.5 ms, whatever the stimulated nerve. The reduced variability and good reproducibility of the ratios I 10/I 50 and I 90/I 50 open perspectives in neurophysiological practice for the use of these indexes of the stimulus-response curve, a rapid and noninvasive test.

Adaptación del Índice de Bienestar Personal para adolescentes en lengua española y portuguesa

The psychometric properties of the Personal Wellbeing Index are analyzed on a Spanish and Portuguese adolescent sample. We test the reliability of the scale using Cronbach’s alpha. And complementarily we analyze the item-total correlations in the different wellbeing domains included. We execute an exploratory factor analysis (principal components) and a multigroup Confirmatory Factor Analysis (CFA). The results show that Cronbach’s alpha is 0.79 for the Chilean version and in the Brazilian version is 0.78 confirming adequate levels of reliability found in previous studies. Correlations between fields of well-being shows values ranging between 0.224 and 0.496 for Chile and from 0.24 to 0.46 for Brazil. The results are similar to those obtained in other countries. The monofactorial structure of the scale is cinfirmed, also the adjustment to the scale structure to the data of the two samples and the comparability of means of global indices. The results suggest the existence of other well-being domains that had not been considered in the original proposal of the scale

Early Detection of Alzheimer's Disease Beta-amyloid Pathology -Applicability of Positron Emission Tomography with the Amyloid Radioligand 11C-PIB

Early Detection of Alzheimer's Disease Beta-amyloid Pathology -Applicability of Positron Emission Tomography with the Amyloid Radioligand ¹¹C-PIB Accumulation of beta amyloid (Abeta) in the brain is characteristic for Alzheimer’s disease (AD). Carbon-11 labeled 2-(4’-methylaminophenyl)-6-hydroxybenzothiazole (¹¹C-PIB) is a novel positron emission tomography (PET) amyloid imaging agent that appears to be applicable for in vivo Abeta plaque detection and quantitation. The biodistribution and radiation dosimetry of ¹¹C-PIB were investigated in 16 healthy subjects. The reproducibility of a simplified ¹¹C-PIB quantitation method was evaluated with a test-retest study on 6 AD patients and 4 healthy control subjects. Brain ¹¹C-PIB uptake and its possible association with brain atrophy rates were studied over a two-year follow-up in 14 AD patients and 13 healthy controls. Nine monozygotic and 8 dizygotic twin pairs discordant for cognitive impairment and 9 unrelated controls were examined to determine whether brain Abeta accumulation could be detected with ¹¹C-PIB PET in cognitively intact persons who are at increased genetic risk for AD. The highest absorbed radiation dose was received by the gallbladder wall (41.5 mjuGy/MBq). About 20 % of the injected radioactivity was excreted into urine, and the effective whole-body radiation dose was 4.7 mjuSv/MBq. Such a dose allows repeated scans of individual subjects. The reproducibility of the simplified ¹¹C-PIB quantitation was good or excellent both at the regional level (VAR 0.9-5.5 %) and at the voxel level (VAR 4.2-6.4 %). ¹¹C-PIB uptake did not increase during 24 months’ follow-up of subjects with mild or moderate AD, even though brain atrophy and cognitive decline progressed. Baseline neocortical ¹¹C-PIB uptake predicted subsequent volumetric brain changes in healthy control subjects (r = 0.725, p = 0.005). Cognitively intact monozygotic co-twins – but not dizygotic co-twins – of memory-impaired subjects exhibited increased ¹¹C-PIB uptake (117-121 % of control mean) in their temporal and parietal cortices and the posterior cingulate (p<0.05), when compared with unrelated controls. This increased uptake may be representative of an early AD process, and genetic factors seem to play an important role in the development of AD-like Abeta plaque pathology. ¹¹C-PIB PET may be a useful method for patient selection and follow-up for early-phase intervention trials of novel therapeutic agents. AD might be detectable in high-risk individuals in its presymptomatic stage with ¹¹C-PIB PET, which would have important consequences both for future diagnostics and for research on disease-modifying treatments.