Contributo para a validação da versão portuguesa da Quebec Back Pain Disability Scale : fiabilidade e poder de resposta em utentes com dor lombar crónica

RESUMO: Um dos principais resultados das intervenções de Fisioterapia dirigidas a utentes com Dor Lombar Crónica (DLC) é reduzir a incapacidade funcional. A Quebec Back Pain Disability Scale (QBPDS) é um instrumento amplamente aceite a nível internacional na medição do nível de incapacidade funcional reportada pelos indivíduos com DLC. O objetivo deste estudo é dar um contributo para a adaptação cultural da versão portuguesa da QBPDS (QBPDS-VP) e investigar o poder de resposta e interpretabilidade da escala. Metodologia: Realizou-se um estudo metodológico, multicentro, baseado num coorte prospetivo de 132 utentes com DLC. Os utentes foram recrutados a partir da lista de espera de 16 serviços de Medicina Física e de Reabilitação/Fisioterapia de várias áreas geográficas de Portugal. A QBPDS- VP foi administrada 3 vezes, em 3 momentos de recolha de dados distintos: T0 - momento inicial (utentes em lista de espera); T1 - 1 semana de intervalo (início dos tratamentos de Fisioterapia); e T2 - 6 semanas de intervalo (pós-intervenção de Fisioterapia). Os dados recolhidos em T0 foram utilizados para a análise fatorial e para o estudo da consistência interna (n=132); os dados da amostra emparelhada de T0 e T1 (n=132) para a fiabilidade teste-reteste; e os dados da amostra emparelhada de T0 e T2 (n=120) para a análise do poder de resposta e interpretabilidade. A âncora externa utilizada foi a perceção global de mudança, neste caso a PGIC- VP, que foi respondida em T1 e T2. O nível de significância para o qual os valores se consideraram satisfatórios foi de p≤ 0,05. O tratamento dos dados foi realizado no software IBM SPSS Statistics (versão 20). Resultados: A QBPDS- VP é uma escala unidimensional, que revela uma excelente consistência interna (α de Cronbach= 0,95) e uma fiabilidade teste-reteste satisfatória (CCI= 0,696; IC 95%: 0,581–0,783). Esta escala demonstrou um poder de resposta moderado, quando aplicada em utentes com DLC ( = 0,426 e AAC= 0,741; IC 95%: 0,645 – 0,837). A Diferença Mínima Detetável (DMD) estimada foi de 19 pontos e as estimativas da Diferença Mínima Clinicamente Importante (DMCI) variaram entre 7 (pelo método curva ROC) e 8 pontos (pelo método “diferença média de pontuação”). A estimativa pela curva ROC deriva do ponto ótimo de corte de 6,5 pontos, com Área Abaixo da Curva (AAC)= 0,741, sensibilidade de 72%, e especificidade de 71%. Uma análise complementar da curva ROC baseada nas diferenças de pontuações da QBPDS, expressa em percentagem, revelou um ponto ótimo de corte de - 24% (AAC= 0,737, sensibilidade de 71%, e especificidade de 71%). Para pontuações iniciais da QBPDS- VP mais altas (≥34 pontos), foi encontrado um ponto ótimo de corte de 10,5 pontos (AAC= 0,738, sensibilidade de 73%, e especificidade de 67%). Conclusão: A QBPDS-VP demonstrou bons níveis de fiabilidade e poder de resposta, recomendando-se o seu uso na medição e avaliação da incapacidade funcional de utentes com DLC. A DMD estimada, de 19 pontos, determinou uma amplitude válida da QBPDS-VP de 19 a 81 pontos. Este estudo propõe estimativas de DMCI da QBPDS- VP numa aplicação específica da escala (em utentes com DLC que são referidos para a intervenção de Fisioterapia). A pontuação inicial da QBPDS- VP deve ser considerada na interpretação de mudanças de pontuação, após a intervenção de Fisioterapia.------------ ABSTRACT: One of the main results of physiotherapy interventions for patients with Chronic Low Back Pain (CLBP) is decrease the functional disability. The Quebec Back Pain Disability Scale (QBPDS) is an instrument widely accepted internationally, in measuring the level of disability reported by individuals with CLBP. The purpose of this study is to contribute to the cultural adaptation of the Portuguese version of QBPDS (QBPDS - PV) and investigate the Responsiveness and Interpretability of QBPDS-PV. Methodology: This was a methodological and multicenter study, based on a sample of 132 subjects with CLBP. The patients were recruited from the waiting lists of 16 medicine rehabilitation service, in many Portugal districts. The Quebec Back Pain Disability Scale was administered in three different moments: T0 – baseline (patients in the waiting list); T1- one week after T0 (the beginning of treatment); and T2 – six weeks after T1 (the posttreatment). The data collected at T0 were used for factor analysis and to study the internal consistency (n = 132); paired sample data of T0 and T1 (n=132) were used for test-retest reliability, and sample data paired for T0 and T2 (n=120) used for responsiveness and interpretability analysis. The external anchor was the global perception of change, measured by the Portuguese version of Patient’s Global Impression of Change (PGIC) Scale. The minimal level of significance established was p ≤ 0,05. Data analysis was performed using the IBM SPSS Statistics software (version 20). Results: The QBPDS-PV is a unidimensional scale, demonstrates an excellent internal consistency (Cronbach's α=0.95) and satisfactory test-retest reliability (ICC= 0.696, 95% CI: 0.581–0.783). The scale revealed moderate responsiveness when applied to patients with CLBP ( = 0.426 and AUC= 0.741, 95% CI: 0.645 - 0.837). The Smallest Detectable Change (SDC) was 19 points, whereas the Minimal Clinically Important Change (MCIC) ranged between 7 (ROC curve method) and 8 points (by the "mean difference score"). The estimate was derived from the ROC curve by an optimal cutoff point of 6.5 points, with Area Under the Curve (AUC)= 0.741, sensitivity 72%, and specificity of 71%. A complementary analysis of the ROC curve based on differences in QBPDS scores from baseline, expressed in percentage, revealed an optimal cutoff point of -24% (AUC= 0.737, sensitivity of 71%, and specificity of 71%). For the highest initial scores of QBPDS-PV (≥ 34 points) was found an optimal cutoff of 10.5 points (AUC= 0.738, sensitivity of 73%, and specificity 67%). Conclusion: The QBPDS-PV demonstrated good levels of reliability and responsiveness, being recommended its use in the measurement and evaluation of disability of patients with CLBP. The SDC of 19 points determined the QBPDS‟ scale width of 19 to 81. This study proposes MCIC values for QBPDS –PV for this specific setting (in CLBP patients who are referred for physiotherapy intervention). The QBPDS –PV baseline score have to be taken into account while interpreting the score change after physiotherapy intervention.

Adaptação cultural e contributo para a validação da escala petterns of activity measura - pain (POAM-P)

RESUMO: A dor lombar crónica (DLC) é uma das condições clínicas mais comuns e com elevados custos socioeconómicos no mundo ocidental. Estudos recentes indicam que os utentes com DLC apresentam diferentes padrões de atividade que influenciam os níveis de incapacidade funcional. Contudo, a evidência acerca destas associações é, ainda, limitada e inconclusiva. Em Portugal, não existe, do nosso conhecimento, nenhuma escala validada para a população portuguesa que meça estes padrões de atividade em utentes com DLC. Objetivos: Adaptar culturalmente a escala Patterns of Activity Measure – Pain (POAM-P) para a população portuguesa com dor lombar crónica inespecífica (DLCI) e contribuir para a sua validação. Metodologia: A versão original (inglesa) do POAM-P foi traduzida e adaptada para a língua portuguesa (POAM-P-VP) através de uma equipa multidisciplinar que incluiu tradutores, retrotradutores (cegos e independentes), peritos de diferentes áreas e utentes com DLCI, de acordo com as recomendações de linhas orientadoras atuais para este processo. A análise factorial e das propriedades psicométricas da POAM-P-VP contou com uma amostra de 132 utentes. A consistência interna foi analisada através do coeficiente alpha de Cronbach (α) e para a análise da fiabilidade teste-reteste recorreu-se ao coeficiente de correlação intraclasse (ICC:2,1). A análise da validade de construto convergente e discriminativa das componentes da POAM-P-VP foi conseguida através da aplicação da versão portuguesa da escala Tampa Scale of Kinesiophobia (TSK-13-VP), e recorrendo ao cálculo do coeficiente de Spearman. Todos os cálculos estatísticos foram realizados no software IBM SPSS Statistics (versão 20). Resultados: A análise factorial permitiu identificar três componentes da POAM-P-VP (evitamento, persistência excessiva e persistência consistente com a dor), sendo estruturalmente diferentes das subescalas do POAM-P original. Estas componentes apresentaram uma consistência interna boa a elevada. As componentes 1 e 2 apresentaram uma fiabilidade teste-reteste moderada a excelente, e a componente 3 uma fiabilidade teste-reteste pobre, limitando o seu poder de uso na prática clínica e em investigação. Relativamente à validade de construto, nenhuma das hipóteses estabelecidas no estudo apriori foram verificadas, não podendo aferir acerca da relação dos padrões de atividade com a cinesiofobia, medida pelo TSK-13-VP. Porém, a componente de evitamento da POAM-P-VP parece medir conteúdos partilhados com a TSK-13-VP (rs = 0.15, p<0.048). Conclusão: A adaptação e contributo para a validação da versão portuguesa da escala POAM-P constituiu um ponto de partida para a existência de um instrumento de medição de padrões de atividade de utentes portugueses com DLC, requerendo mais estudos para a sua validação. Apesar de algumas limitações, considera-se que este estudo é de grande importância para os fisioterapeutas e investigadores que buscam um maior conhecimento e efetividade das abordagens de intervenção em utentes com dor lombar crónica.-------------- ABSTRACT: Chronic low back pain (CLBP) is one of the most common clinical conditions as well as one with high economical costs within western countries. Recent studies have shown that patients with LBP present different patterns of activity which influence their levels of functional capacity. However, evidence on these associations is still limited and inconclusive. To our knowledge, there is in Portugal no valid scale for measuring these patterns of activity in CLBP patients. Purpose: Culturally adapt the Patterns of Activity Measure – Pain (POAM-P) scale to the Portuguese population with non-specific chronic low back pain (NSLBP) and contribute to its validation. Method: The original English version of POAM-P was blindly and independently translated, back translated and adapted to the Portuguese language (POAM-P-VP) by a multidisciplinary team of translators, experts from different fields, and patients with NSLBP, according to established guidelines for this process. Factorial and psychometric properties’ analysis of POAM-P-VP comprised a sample of 132 patients. The internal consistency was analyzed based on Cronbach's alpha-coefficient (α) and for test-retest reliability analysis the Intraclass Correlation Coefficient (ICC) was used. The analysis of convergent and discriminant construct validity of POAM-P-VP components was achieved through the use of the Portuguese version of the Tampa Scale of Kinesiophobia (TSK-13-VP), using the Spearman coefficient calculation. All statistical calculations were performed using IBM SPSS Statistics software (v.20). Results: The factor analysis allowed for the identification of three components of POAM-P-VP (avoidance, excessive persistence and pain-contingent persistence), structurally different from the original POAM-P subscales. These components demonstrated a good to high level of internal consistency. Components 1 and 2 demonstrated moderate to excellent test-retest reliability, whereas component 3 presented low test-retest reliability thus limiting its clinical and investigative use. With regard to construct validity, none of the previously established hypothesis was verified, therefore not making it possible to assess the relation between activity patterns and kinesiophobia, measured by TSK-13-VP. However, the avoidance component of POAM-P-VP seems to share measurable contents with TSK-13-VP (rs = 0.15, p<0.048). Conclusion: The adaptation and contribution to the validation of the Portuguese version of POAM-P scale, sets a starting point to the existence of a useful instrument for measuring activity patterns in Portuguese CLBP patients, requiring further studies towards its validation. Despite some limitations, this study is considered of high importance to physiotherapists as well as investigators in search of deeper knowledge and effective practical approaches on chronic low back pain patients.

Adaptation as a part of system resilience. insights from fish producers organizations in Portugal

Complex problems of globalized society challenge its adaptive capacity. However, it is precisely the nature of these human induced problems that provide enough evidence to show that adaptability may not be on a resilient path. This thesis explores the ambiguity of the idea of adaptation (and its practice) and illustrates the ways in which adaptability contributes to resilience of social ecological systems. The thesis combines a case study and grounded theory approach and develops an analytical framework to study adaptability in resource users’ organizations: from what it depends on and what the key challenges are for resource management and system resilience. It does so for the specific case of fish producers’ organizations (POs) in Portugal. The findings suggest that while ecological and market context, including the type of crisis, may influence the character of fishers’ adaptation within POs (i.e. anticipatory, maladaptive and reactively adaptive), it does not determine it. Instead, it makes agency even more crucial (i.e. leadership, trust and agent’s perceptions in terms of their impact on fishers’ motivation to learn from each other). In sum, it was found that internal adaptation can improve POs’ contribution to fishery management and resilience, but it is not a panacea and may, in some cases, increase system vulnerability to change. Continuous maladaptation of some Portuguese POs points at a basic institutional problem (fish market regime), which clearly reduces fisheries resilience as it promotes overfishing. However, structural change may not be sufficient to address other barriers to Portuguese fishers’ (PO members) adaptability, such as history (collective memory) and associated problematic self-perceptions. The agency (people involved in structures and practices) also needs to change. What and how institutional change and agency change build on one another (e.g. comparison of fisheries governance in Portugal and other EU countries) is a topic to be explored in further research.

Image processing for displacement measurements

Since the invention of photography humans have been using images to capture, store and analyse the act that they are interested in. With the developments in this field, assisted by better computers, it is possible to use image processing technology as an accurate method of analysis and measurement. Image processing's principal qualities are flexibility, adaptability and the ability to easily and quickly process a large amount of information. Successful examples of applications can be seen in several areas of human life, such as biomedical, industry, surveillance, military and mapping. This is so true that there are several Nobel prizes related to imaging. The accurate measurement of deformations, displacements, strain fields and surface defects are challenging in many material tests in Civil Engineering because traditionally these measurements require complex and expensive equipment, plus time consuming calibration. Image processing can be an inexpensive and effective tool for load displacement measurements. Using an adequate image acquisition system and taking advantage of the computation power of modern computers it is possible to accurately measure very small displacements with high precision. On the market there are already several commercial software packages. However they are commercialized at high cost. In this work block-matching algorithms will be used in order to compare the results from image processing with the data obtained with physical transducers during laboratory load tests. In order to test the proposed solutions several load tests were carried out in partnership with researchers from the Civil Engineering Department at Universidade Nova de Lisboa (UNL).

Semantic adaptability for the systems interoperability

In the current global and competitive business context, it is essential that enterprises adapt their knowledge resources in order to smoothly interact and collaborate with others. However, due to the existent multiculturalism of people and enterprises, there are different representation views of business processes or products, even inside a same domain. Consequently, one of the main problems found in the interoperability between enterprise systems and applications is related to semantics. The integration and sharing of enterprises knowledge to build a common lexicon, plays an important role to the semantic adaptability of the information systems. The author proposes a framework to support the development of systems to manage dynamic semantic adaptability resolution. It allows different organisations to participate in a common knowledge base building, letting at the same time maintain their own views of the domain, without compromising the integration between them. Thus, systems are able to be aware of new knowledge, and have the capacity to learn from it and to manage its semantic interoperability in a dynamic and adaptable way. The author endorses the vision that in the near future, the semantic adaptability skills of the enterprise systems will be the booster to enterprises collaboration and the appearance of new business opportunities.