Reliability and concurrent validity of the Global Physical Activity Questionnaire in adults from a Brazilian rural area / Teste-reteste e validade concorrente do Questionário Global de Atividade Física em adultos de uma população rural no Brasil

The aim of this study was to test reliability of the Global Physical Activity Questionnaire (GPAQ), and its concurrent validity using accelerometers, in a Brazilian rural population. Fifty-five adults (18+ years) living in a rural Brazilian city were selected to wear an accelerometer for one week and to an-swer the GPAQ twice in a week period interval. Reliability was verified using Intraclass Correlation Coefficients and the concurrent validity was analyzed based on Bland and Altman's diagrams. We found relatively high reliability for the total physical activity (ICC = 0.78; 95%CI: 0.63; 0.87). The average difference between both GPAQ measures was 192 minutes (95%CI: -69.63; 453.75). Wider differences were found when participants reported > 400 minutes of physical activity per week. There was limited agreement between the GPAQ and accelerometer measures (total average difference = -1043 minutes; 95%CI: -1452.23; -634.09). Thus, the questionnaire presented limited concurrent validity and acceptable reliability, being able to be used in rural populations. However, there is still a need of new physical activity instruments focused on rural populations

O objetivo deste estudo foi realizar um teste-reteste do Questionário Global de Atividade Física (GPAQ) e sua validade concorrente com acelerômetros em uma população rural brasileira. Cinquenta e cinco adultos (18 anos ou mais) moradores da área rural da cidade de Arroio do Padre foram selecionados para responder o GPAQ em duas semanas subsequentes e usar um acelerômetro por uma semana. Para realizar o teste-reteste foi usado o coeficiente de correlação intraclasse (CCI) e a validade concorrente foi analisada usando gráficos Bland and Altman. O resultado do teste-reteste de atividade física total foi alto (CCI = 0,78; IC95%: 0,63; 0,87). A diferença média entre as duas medidas do GPAQ foi 192 minutos (IC95%: -69.63; 453.75). Maiores diferenças foram encontradas quando os participantes reportaram praticar mais de 400 minutos de atividade física por semana. A concordância foi limitada entre as medidas do GPAQ e do acelerômetro (diferença média total = -1043 minutos; IC95%: -1452.23; -634.09). Logo, o GPAQ apresentou limitada validade concorrente e aceitável teste-reteste, podendo ser usado em populações rurais. Contudo, a criação de um novo instrumento de atividade física focado na população rural é necessária

The Availability of Radiological Measurement of Tibial Torsion: Three-Dimensional Computed Tomography Reconstruction

OBJECTIVE: To assess the intra-rater and inter-rater reliability for measuring tibial torsion measurements by a radiographic method using three-dimensional computed tomography reconstruction (3D-CT) and to compare the physical measures to those of 3D-CT. METHOD: The study included 33 children who presented with intoeing gait. Tibial torsion was measured by 3D-CT. Distal reference point was the bimalleolar axis. Proximal reference points were the transtibial axis and posterior condylar axis. Physical measurements included thigh-foot angle (TFA) and bimalleolar angle (BMA). 3D-CT measurement and physical measurement were performed twice at both lower extremities by each rater. The intra-rater and inter-rater reliability were calculated by intraclass correlation coefficiency (ICC). The relationship between radiological and physical examination was calculated by Spearman correlation coefficient. RESULTS: The 3D-CT measures for tibial torsion were reliable within individual raters and between different raters. However, physical measures for tibial torsion were reliable within an individual rater but not reliable between raters. The 3D-CT measures by any proximal reference axis were more reliable within a rater and between raters than physical measurements. There was no significant impact introduced by the selection of the proximal reference axis. The correlation coefficiency between 3D-CT and physical measurement methods was low. CONCLUSION: Because the 3D-CT measurements for tibial torsion are more reliable than physical measurements, we recommend that accurate diagnosis of internal tibial torsion should be detected by using 3D-CT measurements. Also, considering the disadvantages of radiological measurements, physical measurement may be used for short term follow-up by same raters, as intra-rater reliability is relatively good.