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INTRODUCTION: Treatment of proximal humerus fractures remains controversial. Understanding the factors that can affect the long-term functional outcomes can aid with management choices. This primary aim of this paper is to evaluate the association of radiographic parameters with functional outcomes. METHODS: Radiographic parameters [Caput-collum-diaphyseal (CCD) angles, Y-scapular angles, and humeral head height (HHH)] were studied. The patients were split into varus and valgus groups based on the CCD angles and retroverted and anteverted groups based on Y-scapular angles. Functional outcome was measured by Oxford Shoulder Score (OSS), Constant Shoulder Score (CSS), and quick Disabilities of Arm, Shoulder and Hand score at 1 year follow-up. Intra- and interrater reliability were measured with the intraclass correlation coefficients (ICCs). Receiver operator curve (ROC) analysis and logistic regression analysis defined the optimal value for abnormalities on radiographic evaluation as an outcome predictor. RESULTS: 111 patients were recruited (mean age 69, 78% female). Median final radiographic assessment was at 7 months. Mean initial/final CCD was 119o /111o (varus, n = 36) and 153o/140o (valgus, n = 75). Mean initial/final Y-scapula angle was 27o/27o (retroversion, n = 101) and 70o/40o (anteversion, n = 9). There was a significant relationship between OSS and final Y-scapular angle in the retroverted group (adj coeff 0.034, p = 0.009) with optimum predictive retroversion angulation of 25o predicting poor functional outcome (OSS < 40), area under the ROC curve of 0.614. Higher initial valgus and retroversion significantly predicted more change in the final angle (adj coeff - 0.349, p = 0.002, adj coeff - 0.527, p < 0.001 respectively). Both intra-rater and inter-rater reliability for the radiographic parameters were excellent (ICC > 0.9). CONCLUSION: Radiographic parameters whilst having excellent reliability, have a limited ability to predict short-term functional recovery. The extent of retroversion is the most important predictor for functional recovery with 25o a cut-off guide. Fractures with a higher initial valgus and retroversion tend to displace more.
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Enfermedades Cardiovasculares/sangre , Enfermedades Cardiovasculares/mortalidad , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/mortalidad , Índices de Eritrocitos , Anciano , Enfermedades Cardiovasculares/diagnóstico , Diabetes Mellitus Tipo 2/diagnóstico , Femenino , Factores de Riesgo de Enfermedad Cardiaca , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico , Medición de Riesgo , Singapur , Factores de TiempoRESUMEN
BACKGROUND: Different study designs and population size may require different sample size for logistic regression. This study aims to propose sample size guidelines for logistic regression based on observational studies with large population. METHODS: We estimated the minimum sample size required based on evaluation from real clinical data to evaluate the accuracy between statistics derived and the actual parameters. Nagelkerke r-squared and coefficients derived were compared with their respective parameters. RESULTS: With a minimum sample size of 500, results showed that the differences between the sample estimates and the population was sufficiently small. Based on an audit from a medium size of population, the differences were within ± 0.5 for coefficients and ± 0.02 for Nagelkerke r-squared. Meanwhile for large population, the differences are within ± 1.0 for coefficients and ± 0.02 for Nagelkerke r-squared. CONCLUSIONS: For observational studies with large population size that involve logistic regression in the analysis, taking a minimum sample size of 500 is necessary to derive the statistics that represent the parameters. The other recommended rules of thumb are EPV of 50 and formula; n = 100 + 50i where i refers to number of independent variables in the final model.
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BACKGROUND: Body self-image questionnaire-short form (BSIQ-SF) is developed to measure body image perceptions. Due to the cultural, language and environmental differences between western and eastern population, the validity and reliability need to be established. The aim of this study was to determine validity and reliability of Malay version BSIQ-SF. METHODS: A cross-sectional study involved web-based survey was employed. Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) was performed using SPSS version 22 and Mplus 7.3. RESULTS: There were 688 young adults in Malaysia with mean age of 23.67 (SD = 0.188) and mean body mass index (BMI) of 23.34 (SD = 0.27) participated in the study. Exploratory factor analysis performed and the number domains reduced from nine to four, namely 'Negative Affect', 'Attractiveness Evaluation', 'Physical Functionality Awareness' and 'Height Dissatisfaction'. CFA further confirmed the structure of the model with adequate goodness-of-fit values [CFI = 0.927, TLI = 0.913, SRMR = 0.075, RMSEA = 0.053 (95% CI: 0.047, 0.060)]. CONCLUSION: The revised 21-item of the Malay version BSIQ-SF was a valid and reliable instrument to measure body image perceptions among Malaysian young adults.