Investigación: acción participativa para evaluar el impacto de la difusión vía online de activos de salud / Research – participatory action to evaluate the impact of the online dissemination of health assets

Antecedentes: La identificación de activos de salud y la difusión de los mismos por parte de los profesionales de Atención Primaria (AP) mejora la calidad de vida de las personas. En este proyecto se pretende dar voz a diversos activos comunitarios del Área Sanitaria de Vigo e iniciar la formación de una red local para la salud en el área. Método: Estudio cualitativo de investigación-acción participativa (IAP). Se hicieron cuatro entrevistas en formato vídeo a asociaciones que trabajan con grupos de población especialmente afectados por la situación sanitaria de pandemia de la COVID-19. Se publicaron en el canal de YouTube de la Unidad Docente de Atención Familiar y Comunitaria (UDAFyC) de Vigo. Se acompañaron de la transcripción de la entrevista y de la documentación facilitada por la propia asociación. Fueron difundidos por el grupo promotor del proyecto y otros recursos externos. Se evaluó el impacto analizando las visualizaciones en cada una de ellas. Resultados: Los vídeos tuvieron una duración media de 10 minutos. El pico de visualizaciones se encuentra entre los 2-3 primeros días tras su publicación y las visitas al canal de YouTube fueron un total de 618, siendo las aplicaciones externas WhatsApp (178) y Facebook (86) las más utilizadas para acceder a la plataforma. Únicamente una de las asociaciones entrevistadas compartió el vídeo realizado en sus redes sociales. Discusión: La mayor parte de la difusión ha sido a través del grupo promotor y de la Unidad Docente Multidisciplinar de Vigo, siendo efectiva la instauración del recurso de difusión vía telemática. La mayoría de los activos comunitarios están dispuestos a colaborar en este tipo de proyectos, aunque no tienen gran peso en la difusión posterior del vídeo. Es importante mantener este tipo de difusiones y evaluaciones en el tiempo para ampliar y mejorar los conocimientos de los activos comunitarios por parte de la población. (AU)

Background. The identification of community assets and their dissemination by primary care professionals improves people's quality of life. Therefore, in this project we tried to give a voice to different community assets in the Vigo Health Area and to start training a local health network in the area. Method. By means of qualitative study research - participatory action we performed four interviews in video format with associations who work with population groups especially affected by the COVID-19 pandemic health situation. They were published on the Vigo Family and Community Attention Teaching unit (UDAFyC) YouTube channel and were disseminated by the group promoting the project and other external resources. Next, we evaluated the impact by analyzing the number of times they were seen. Results. The videos lasted on average 10 minutes. The peak number of views was between the first two to three days after their publication and the YouTube channel received a total of 618 visits; WhatsApp and Facebook being the applications most used to access the platform. Only one association interviewed shared the video on their social networks. Discussion. Most dissemination was by means of the promoter group and the Vigo Multidisciplinary Teaching Unit. Establishment of the online dissemination resource was effective. Most community assets are willing to collaborate in this type of project, although they do not have a great weight in subsequent dissemination of the video. It is important to maintain this type of dissemination and evaluations over time to expand and improve the knowledge of community assets by the population. Conclusions. In total, the channel received a total of 618 visits with external sources such as WhatsApp and Facebook being the most used for access. (AU)

Small static radiosurgery field dosimetry with small volume ionization chambers.

PURPOSE: To evaluate the response of the four smallest active volume thimble type ionization chambers commercially available (IBA-dosimetry RAZOR Nano Chamber, Standard Imaging Exradin A16, IBA-dosimetry CC01 and PTW T31022) when measuring SRS cone collimated Flattening Filter Free (FFF) fields. METHODS: We employed Monte Carlo simulation for calculating correction factors as defined in IAEA TRS-483. Monte Carlo simulation beam model and ion chamber geometry definitions were supported by an extensive set of measurements. Type A and B uncertainty components were evaluated. RESULTS: Commissioning of Monte Carlo 6 MV and 10 MV FFF beam models yielded relative differences between measured and simulated dose distributions lower than 1.5%. Monte Carlo simulated output factors for 5 mm SRS field agree with experimental values within 1% local relative difference for all chambers. Smallest active volume ion chamber (IBA-dosimetry RAZOR Nano Chamber) exhibits smallest correction, being compatible with unity. Correction factor combined uncertainties range between 0.7% and 0.9%. Smallest uncertainties were recorded for smallest and largest active volume ion chambers, although the latter exhibited largest correction factor. Highest contribution to combined uncertainty was type B component associated with beam model initial electron spatial Full Width Half Maximum (FWHM) uncertainty. CONCLUSIONS: Among the investigated chambers, the IBA RAZOR Nano Chamber was found to be an excellent choice for narrow beam output factor measurement since it requires minimum correction (in line with IAEA TRS-483 recommendations). This is caused by its tiny size and tissue equivalence materials which produce minimum volume averaging and fluence perturbation.

An EGS Monte Carlo model for Varian TrueBEAM treatment units: Commissioning and experimental validation of source parameters.

In this work we have created and commissioned a Monte Carlo model of 6FFF Varian TrueBeam linear accelerator using BEAMnrc. For this purpose we have experimentally measured the focal spot size and shape of three Varian TrueBeam treatment units in 6FFF modality with a slit collimator and several depth dose and lateral beam profiles in a water phantom. The Monte Carlo model of a 6FFF TrueBeam machine was implemented with a primary electron source commissioned as a 2D Gaussian with Full Width Half Maximum selected by comparison of simulated and measured narrow beam profiles. The energy of the primary electron beam was optimized through a simultaneous fit to the measured beam depth dose profiles. Special attention was paid to evaluation of uncertainties of the selected Monte Carlo source parameters. These uncertainties were calculated by analysing the sensitivity of the commissioning process to changes in both primary beam size and energy. Both experimental and Monte Carlo commissioned focus size values were compared and found to be in excellent agreement. The commissioned Monte Carlo model reproduces within 1% accuracy the dose distributions of radiation field size from 3 cm × 3 cm to 15 cm × 15 cm.