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- Adapted control methods for cerebral palsy users of an intelligent wheelchairPublication . Faria, Brigida Monica; Reis, Luis Paulo; Lau, NunoThe development of an intelligent wheelchair (IW) platform that may be easily adapted to any commercial electric powered wheelchair and aid any person with special mobility needs is the main objective of this project. To be able to achieve this main objective, three distinct control methods were implemented in the IW: manual, shared and automatic. Several algorithms were developed for each of these control methods. This paper presents three of the most significant of those algorithms with emphasis on the shared control method. Experiments were performed by users suffering from cerebral palsy, using a realistic simulator, in order to validate the approach. The experiments revealed the importance of using shared (aided) controls for users with severe disabilities. The patients still felt having complete control over the wheelchair movement when using a shared control at a 50% level and thus this control type was very well accepted. Thus it may be used in intelligent wheelchairs since it is able to correct the direction in case of involuntary movements of the user but still gives him a sense of complete control over the IW movement.
- Adaptive model for biofeedback data flows management in the design of interactive immersive environmentsPublication . Gomes, Paulo Veloso; Marques, António; Donga, João; Sá, Catarina; Correia, António; Pereira, JavierThe interactivity of an immersive environment comes up from the relationship that is established between the user and the system. This relationship results in a set of data exchanges between human and technological actors. The real-time biofeedback devices allow to collect in real time the biodata generated by the user during the exhibition. The analysis, processing and conversion of these biodata into multimodal data allows to relate the stimuli with the emotions they trigger. This work describes an adaptive model for biofeedback data flows management used in the design of interactive immersive systems. The use of an affective algorithm allows to identify the types of emotions felt by the user and the respective intensities. The mapping between stimuli and emotions creates a set of biodata that can be used as elements of interaction that will readjust the stimuli generated by the system. The real-time interaction generated by the evolution of the user’s emotional state and the stimuli generated by the system allows him to adapt attitudes and behaviors to the situations he faces.
- Advancing the understanding of pupil size variation in occupational safety and health: A systematic review and evaluation of open-source methodologiesPublication . Ferreira, Filipa; Ferreira, Simão; Mateus, Catarina; Rocha, Nuno; Coelho, Luís; Rodrigues, MatildePupil size can be used as an important biomarker for occupational risks. In recent years, there has been an increase in the development of open-source tools dedicated to obtaining and measuring pupil diameter. However, it remains undetermined determined whether these tools are suitable for use in occupational settings. This study explores the significance of pupil size variation as a biomarker for occupational risks and evaluates existing open-source methods for potential use in both research and occupational settings, with the goal of to prevent occupational accidents and improve the health and performance of workers. To this end, a two-phase systematic literature review was conducted in the Web of Science™, ScienceDirect®, and Scopus® databases. For the relevance of monitoring pupil size variation in occupational settings, 15 articles were included. The articles were divided into three groups: mental workload, occupational stress, and mental fatigue. In most cases, pupil dilation increased with workload enhancement and with higher levels of stress. Regarding fatigue, it was noted that an increase in this condition corresponded with a decrease in pupil size. With respect to the open-source methodologies, 16 articles were identified, which were categorized into two groups: algorithms and software. Convolutional neural networks (CNN)1 have exhibited superior performance among the various algorithmic approaches studied. Building on this insight, and considering the evaluations of software options, MEYE emerges as the premier open-source system for deployment in occupational settings due to its compatibility with a standard computer webcam. This feature positions MEYE as a particularly practical tool for workers in stable environments, like those of developers and administrators.
- Affinity coefficient for clustering autoregressive moving average modelsPublication . Nascimento, Ana Paula; Oliveira, Alexandra; Faria, Brígida Mónica; Pimenta, Rui; Vieira, Mónica; Prudêncio, Cristina; Nicolau, Helena BacelarIn various fields, such as economics, finance, bioinformatics, geology, and medicine, namely, in the cases of electroencephalogram, electrocardiogram, and biotechnology, cluster analysis of time series is necessary. The first step in cluster applications is to establish a similarity/dissimilarity coefficient between time series. This article introduces an extension of the affinity coefficient for the autoregressive expansions of the invertible autoregressive moving average models to measure their similarity between them. An application of the affinity coefficient between time series was developed and implemented in R. Cluster analysis is performed with the corresponding distance for the estimated simulated autoregressive moving average of order one. The primary findings indicate that processes with similar forecast functions are grouped (in the same cluster) as expected concerning the affinity coefficient. It was also possible to conclude that this affinity coefficient is very sensitive to the behavior changes of the forecast functions: processes with small different forecast functions appear to be well separated in different clusters. Moreover, if the two processes have at least an infinite number of π- weights with a symmetric signal, the affinity value is also symmetric.
- Age-period-cohort effects in the incidence of hip fractures: political and economic events are coincident with changes in riskPublication . Alves, Sandra Maria; Castiglione, Débora; Oliveira, Carla Maria; Sousa, Bruno; Pina, Maria De FátimaIntroduction: Healthcare improvements have allowed prevention but have also increased life expectancy, resulting in more people being at risk. Our aim was to analyse the separate effects of age, period and cohort on incidence rates by sex in Portugal, 2000–2008. Methods: From the National Hospital Discharge Register, we selected admissions (aged ≥49 years) with hip fractures (ICD9-CM, codes 820.x) caused by low/moderate trauma (falls from standing height or less), readmissions and bone cancer cases. We calculated person-years at risk using population data from Statistics Portugal. To identify period and cohort effects for all ages, we used an age–period–cohort model (1-year intervals) followed by generalised additive models with a negative binomial distribution of the observed incidence rates of hip fractures. Results: There were 77,083 hospital admissions (77.4 % women). Incidence rates increased exponentially with age for both sexes (age effect). Incidence rates fell after 2004 for women and were random for men (period effect). There was a general cohort effect similar in both sexes; risk of hip fracture altered from an increasing trend for those born before 1930 to a decreasing trend following that year. Risk alterations (not statistically significant) coincident with major political and economic change in the history of Portugal were observed around birth cohorts 1920 (stable–increasing), 1940 (decreasing–increasing) and 1950 (increasing–decreasing only among women). Conclusions: Hip fracture risk was higher for those born during major economically/politically unstable periods. Although bone quality reflects lifetime exposure, conditions at birth may determine future risk for hip fractures.
- An investigation of digital skills of therapeutic radiographers/radiation therapists: A european survey of proficiency level and future educational needsPublication . Barbosa, B.; Oliveira, C.; Bravo, I.; Couto, G.; Antunes, L.; McFadden, S.; Hughes, C.; McClure, P.; Rodrigues, J.; Dias, A.G.This study aims to assess the proficiency level of digital skills, the factors influencing that level and the training needs of Therapeutic Radiographers/Radiation Therapists (TR/RTTs), due to the differences in technology availability and accessibility, variations in the regulation and education of TR/RTTs in European countries, and the lack of a digital skills framework. An online survey was distributed to TR/RTTs working in Europe to capture their self assessment of proficiency levels of digital skills when performing their clinical role. Information was also gathered regarding training, work experience and level of information and communication tech nology (ICT) skills. Quantitative measures were analysed using descriptive statistics and correlation between variables, and qualitative responses using thematic analysis. 101 respondents from 13 European countries completed the survey. Digital skills in treatment planning followed by management and research were the least developed skills, while the most developed were transversal digital skills followed by digital skills in treatment delivery. The Radio therapy areas of practice where TR/RTT has experience (e.g. Planning Image, Treatment Planning, Treatment), as well as the level of generic ICT skills (communication, content creation and problem solving), was related to the level of proficiency of TR/RTT digital skills. Greater scope of practice and level of generic ICT were associated with a higher level of TR/RTT digital skills. Thematic analysis allowed the identification of new sub-themes to be included in the training of TR/RTTs. Education and training of TR/RTTs should be improved and adapted to the current needs of digitalisation to avoid differences in digital proficiency levels. Implications for practice: Aligning TR/RTTs’ digital skill sets with emerging digitalisation will improve current practice and ensure the best care to all RT patients.
- Analyzing multiple outcomes: is it really worth the use of multivariate linear regression?Publication . Oliveira, Rosa; Teixeira-Pinto, ArmandoIn health related research it is common to have multiple outcomes of interest in a single study. These outcomes are often analysed separately, ignoring the correlation between them. One would expect that a multivariate approach would be a more efficient alternative to individual analyses of each outcome. Surprisingly, this is not always the case. In this article we discuss different settings of linear models and compare the multivariate and univariate approaches. We show that for linear regression models, the estimates of the regression parameters associated with covariates that are shared across the outcomes are the same for the multivariate and univariate models while for outcome-specific covariates the multivariate model performs better in terms of efficiency.
- Applications of brain wave classification for controlling an intelligent wheelchairPublication . Avelar, Maria Carolina; Almeida, Patricia; Faria, Brígida Mónica; Reis, Luís PauloThe independence and autonomy of both elderly and disabled people have been a growing concern in today’s society. Therefore, wheelchairs have proven to be fundamental for the movement of these people with physical disabilities in the lower limbs, paralysis, or other type of restrictive diseases. Various adapted sensors can be employed in order to facilitate the wheelchair’s driving experience. This work develops the proof concept of a brain–computer interface (BCI), whose ultimate final goal will be to control an intelligent wheelchair. An event-related (de)synchronization neuro-mechanism will be used, since it corresponds to a synchronization, or desynchronization, in the mu and beta brain rhythms, during the execution, preparation, or imagination of motor actions. Two datasets were used for algorithm development: one from the IV competition of BCIs (A), acquired through twenty-two Ag/AgCl electrodes and encompassing motor imagery of the right and left hands, and feet; and the other (B) was obtained in the laboratory using an Emotiv EPOC headset, also with the same motor imaginary. Regarding feature extraction, several approaches were tested: namely, two versions of the signal’s power spectral density, followed by a filter bank version; the use of respective frequency coefficients; and, finally, two versions of the known method filter bank common spatial pattern (FBCSP). Concerning the results from the second version of FBCSP, dataset A presented an F1-score of 0.797 and a rather low false positive rate of 0.150. Moreover, the correspondent average kappa score reached the value of 0.693, which is in the same order of magnitude as 0.57, obtained by the competition. Regarding dataset B, the average value of the F1-score was 0.651, followed by a kappa score of 0.447, and a false positive rate of 0.471. However, it should be noted that some subjects from this dataset presented F1-scores of 0.747 and 0.911, suggesting that the movement imagery (MI) aptness of different users may influence their performance. In conclusion, it is possible to obtain promising results, using an architecture for a real-time application.
- Assessing the efficacy of the ‘Bicho De 7 Cabeças’ B-learning school-based program in enhancing mental health literacy and reducing stigmaPublication . Meilsmeidth, Gislene; Trigueiro, Maria João; Simões-Silva, Vítor; Simões de Almeida, Raquel; Portugal, Paula; Gomes, Paulo Veloso; Sousa, Sara; Campos, Filipa; Monteiro, Pedro; Soutelo, Ana Paula; Marques, AntónioThe prevalence of mental disorders in adolescents has a considerable impact on daily life, restricting tasks and diminishing overall quality of life while potentially leading to stigmatization. This study aims to measure the impact of a mental health literacy intervention program, called “Bicho de 7 Cabeças” project, in b-learning format, on the increase of knowledge and the decrease of stigma in young people from Póvoa de Varzim, in Portugal. A quasi-experimental study was conducted, from November 2022 to May 2023, involving an experimental group (“Bicho de 7 Cabeças” protocol) and an active control group (informational brochures), utilizing a pre-test/post-test design. Mental Health Literacy Measure-MHLM, Mental Health Promoting Knowledge Scale-MHPK-10, Mental Illness Knowledge Schedule-MAKS, Reported and Intended Behaviour Scale-RIBS, and Community Attitudes toward People with Mental Illness-CAMI were used. A total of 504 young students from the 9th grade enroll in this study, with a mean age around 14 years old. There is a significant difference between stigma (p <.001) and knowledge (p <.001) scores at baseline and follow-up. The results of this study shows that interventions aimed at young people for the promotion of mental health literacy and stigma reduction are needed and more initiatives should be implemented in schools to address these problems.
- Atitudes face à estatística em diferentes grupos de profissionais de saúde em formaçãoPublication . Pimenta, Rui; Pereira, Ilídio; Costa, Elísio; Vieira, MargaridaUma grande parte das decisões que os profissionais de saúde tomam no seu dia-a-dia tem suporte estatístico num modelo que integre a prática clínica baseada na evidência. A atitude que estes profissionais têm face à estatística pode condicionar o exercício da competência estatística na sua prática clínica e o correcto desenvolvimento da intuição estatística. Neste trabalho, analisámos as diferentes componentes das atitudes face à estatística de estudantes e profissionais em formação, em distintas áreas de formação clínica e em distintos ciclos formativos, através das suas respostas ao Inquérito Atitudes Face à Estatística (SATS 28). Pretendemos, em primeiro lugar, avaliar a e analisar a relação entre as componentes das atitudes na nossa amostra. De seguida, recorremos a técnicas de visualização radial para verificar que componentes das atitudes permitem explicar melhor a variação das respostas dos estudantes. Por último, pretendemos comparar as atitudes face à estatística em diferentes grupos de profissionais em formação tomando em linha de conta a sua situação face à graduação. Recorremos a uma análise de variância a dois factores para estudar a interacção entre os factores área de formação e situação face à graduação e comparar os resultados obtidos nos diferentes grupos que decorrem desta análise. Os nossos resultados mostram que os estudantes das ciências da saúde têm, geralmente, uma atitude positiva face à estatística embora a dificuldade percebida seja mais relevante do que em estudos realizados anteriormente noutras áreas de formação.