ACTIVLIM: adaptación transcultural al castellano y validación en adultos con miopatías hereditarias utilizando el modelo Rasch / Transcultural adaptation and validation of the Spanish-language version of ACTIVLIM in adults with inherited myopathies using the Rasch model

Introducción: ACTIVLIM es un instrumento de medición de la limitación funcional en pacientes con enfermedades neuromusculares. El objetivo de este estudio es la adaptación transcultural y la validación psicométrica de la versión en castellano del ACTIVLIM en una muestra española de pacientes con miopatías hereditarias.Pacientes y métodoSe elaboró una versión en castellano del cuestionario ACTIVLM mediante el método de traducción-retrotraducción. El cuestionario obtenido fue cumplimentado por 135 pacientes con miopatías hereditarias. Las propiedades psicométricas del mismo fueron evaluadas mediante el modelo Rasch. Se valoró la adecuación del rango mediante la estimación de efectos techo y suelo; la unidimensionalidad mediante análisis de componentes principales de los residuales del modelo y estadísticos infit y outfit; la fiabilidad mediante el índice de fiabilidad asociado al índice de separación y la invarianza mediante la estimación del funcionamiento diferencial. Asimismo, la validez de constructo se evaluó estimando la correlación con las escalas de Brooke, de Vignos, la medida de independencia funcional y el tiempo de Gowers, y la fiabilidad test-retest mediante el índice de correlación intraclase y con el plot del funcionamiento diferencial del ítem.ResultadosEl análisis psicométrico de la versión en castellano del ACTIVLIM demostró ausencia de efecto suelo y moderado efecto techo, unidimensionalidad, una buena consistencia interna, validez externa de constructo y buena fiabilidad test-retest.ConclusiónLa versión en castellano del ACTIVLIM es un instrumento de medición válido y fiable para evaluar las limitaciones en la actividad en pacientes con miopatías hereditarias. (AU)

Introduction: ACTIVLIM is an instrument for the measurement of activity limitations in patients with neuromuscular disorders. The aim of this study is to establish a transcultural adaptation and psychometric validation of the Spanish-language version of ACTIVLIM in a sample of Spanish patients with inherited myopathies.Patients and methodA Spanish-language version of ACTIVLIM was developed using the translation/back translation method. The questionnaire was administered to 135 patients with inherited myopathies. The psychometric properties of the questionnaire were assessed using the Rasch model. Floor and ceiling effects were estimated. Unidimensionality was evaluated with a principal component analysis of the residuals of the model, and using infit and outfit statistics. We estimated reliability with the person separation reliability index and invariance with differential item functioning. External construct validity was tested through correlation with the Brooke scale, the Vignos scale, the Functional Independence Measure scale, and floor-to-stand time. Test-retest reliability was evaluated with the intraclass correlation coefficient and differential item functioning.ResultsThe psychometric analysis of the Spanish-language version of ACTIVLIM demonstrated that floor effect was absent, although a modest ceiling effect was identified. The instrument displayed unidimensionality, good internal consistency, external construct validity, and good test-retest reliability.ConclusionThe Spanish-language version of ACTIVLIM is a valid and reliable measurement nstrument for assessing activity limitations in patients with inherited myopathies. (AU)

Transcultural adaptation and validation of the Spanish-language version of ACTIVLIM in adults with inherited myopathies using the Rasch model.

INTRODUCTION: ACTIVLIM is an instrument for the measurement of activity limitations in patients with neuromuscular disorders. The aim of this study is to establish a transcultural adaptation and psychometric validation of the Spanish-language version of ACTIVLIM in a sample of Spanish patients with inherited myopathies. PATIENTS AND METHOD: A Spanish-language version of ACTIVLIM was developed using the translation/back translation method. The questionnaire was administered to 135 patients with inherited myopathies. The psychometric properties of the questionnaire were assessed using the Rasch model. Floor and ceiling effects were estimated. Unidimensionality was evaluated with a principal component analysis of the residuals of the model, and using infit and outfit statistics. We estimated reliability with the person separation reliability index and invariance with differential item functioning. External construct validity was tested through correlation with the Brooke scale, the Vignos scale, the Functional Independence Measure scale, and floor-to-stand time. Test-retest reliability was evaluated with the intraclass correlation coefficient and differential item functioning. RESULTS: The psychometric analysis of the Spanish-language version of ACTIVLIM demonstrated that floor effect was absent, although a modest ceiling effect was identified. The instrument displayed unidimensionality, good internal consistency, external construct validity, and good test-retest reliability. CONCLUSION: The Spanish-language version of ACTIVLIM is a valid and reliable measurement instrument for assessing activity limitations in patients with inherited myopathies.

Nano-cones for broadband light coupling to high index substrates.

The moth-eye structure has been proposed several times as an antireflective coating to replace the standard optical thin films. Here, we experimentally demonstrate the feasibility of a dielectric moth-eye structure as an antireflective coating for high-index substrates, like GaAs. The fabricated photonic crystal has Si3N4 cones in a square lattice, sitting on top of a TiO2 index matching layer. This structure attains 1.4% of reflectance power losses in the operation spectral range of GaAs solar cells (440-870 nm), a 12.5% relative reduction of reflection power losses in comparison with a standard bilayer. The work presented here considers a fabrication process based on laser interference lithography and dry etching, which are compatible with solar cell devices. The experimental results are consistent with scattering matrix simulations of the fabricated structures. In a broader spectral range (400-1800 nm), the simulation estimates that the nanostructure also significantly outperforms the standard bilayer coating (3.1% vs. 4.5% reflection losses), a result of interest for multijunction tandem solar cells.

Prospective serological study of leptospirosis in southern Spain.

This article reports data concerning a serosurvey carried out in Southern Spain to assess the current epidemiological status of a population exposed to risk of leptospirosis. Microagglutination and IgM-EIA tests were carried out on sera from a sample of workers in agriculture-related occupations, exposed to marsh waters. A cohort of 197 workers were followed for a year in an active surveillance program to evaluate seroconversion (laboratory confirmed leptospirosis). The results have shown for the cohort a density of incidence: 6.4 x 100 persons per year, and for the reference population an accumulated incidence of 41.25/100,000. Prevalence rates (P) were 21.3 x 100 and 144 x 10(5) for the cohort and population respectively. Rates were higher in cray-fishers (P: 62.7%), rice-workers, and butchers. This is the first report identifying cray-fishers as a high risk group for leptospirosis, and the reporting of human contamination by Australis serogroup in Spain.