Logistic Regression and Linear Discriminant Analyses in Evaluating Factors Associated with Asthma Prevalence among 10- to 12-Years-Old Children: Divergence and Similarity of the Two Statistical Methods

Logistic regression and discriminant analyses are both applied in order to predict the probability of a specific categorical outcome based upon several explanatory variables (predictors). The aim of this work is to evaluate the convergence of these two methods when they are applied in data from the health sciences. For this purpose, we modeled the association of several factors with the prevalence of asthma symptoms with both the two methods and compared the result. In conclusion, logistic and discriminant analyses resulted in similar models

Reliability and validity of the KIDSCREEN-52 health-related quality of life questionnaire in a Greek adolescent population

<p>Abstract</p> <p>Background</p> <p>The KIDSCREEN-52 is a worldwide instrument for measuring health-related quality of life (HRQoL) in children and adolescents. The aim of this study is to assess reliability and validity of the Greek version of KIDSCREEN.</p> <p>Methods</p> <p>Questionnaires were collected from a representative nationwide sample of 1,194 adolescents aged from 11 to 17 years. Internal consistency reliability was determined by calculation of the Cronbach α coefficient. A confirmatory factor analysis (CFA) was conducted in order to test the construct validity of the questionnaire. Validity was further examined by investigating the correlation of KIDSCREEN with the Strengths and Difficulties Questionnaire (SDQ) and its association with socioeconomic and health-related factors.</p> <p>Results</p> <p>Internal consistency reliability was accepted with a Cronbach α above 0.73 for all KIDSCREEN dimensions. CFA showed that the ten-dimensional model fitted the data well (root mean square error of approximation (RMSEA) = 0.048, comparative fit index (CFI) = 0.971 and goodness of fit index (GFI) = 0.965). Correlation coefficients between KIDSCREEN and SDQ dimensions were significant. Adolescents of low socioeconomic status reported lower scores in the majority of KIDSCREEN dimensions. Also, adolescents with chronic health problem had poorer quality of life concerning physical well-being and other dimensions of KIDSCREEN.</p> <p>Conclusions</p> <p>The Greek version of KIDSCREEN-52 was found to have satisfied psychometric properties and could be suitable for assessing HRQoL in Greek adolescents.</p

The relationship between dietary fat intake and risk of colorectal cancer: evidence from the combined analysis of 13 case-control studies

The objective of this study was to examine the effects of the intakeof dietary fat upon colorectal cancer risk in a combined analysis of datafrom 13 case-control studies previously conducted in populations withdiffering colorectal cancer rates and dietary practices. Original datarecords for 5,287 cases of colorectal cancer and 10,470 controls werecombined. Logistic regression analysis was used to estimate odds ratios (OR)for intakes of total energy, total fat and its components, and cholesterol.Positive associations with energy intake were observed for 11 of the 13studies. However, there was little, if any, evidence of anyenergy-independent effect of either total fat with ORs of 1.00, 0.95, 1.01,1.02, and 0.92 for quintiles of residuals of total fat intake (P trend =0.67) or for saturated fat with ORs of 1.00, 1.08, 1.06, 1.21, and 1.06 (Ptrend = 0.39). The analysis suggests that, among these case-control studies,there is no energy-independent association between dietary fat intake andrisk of colorectal cancer. It also suggests that simple substitution of fatby other sources of calories is unlikely to reduce meaningfully the risk ofcolorectal cancer.Facultad de Ciencias Médica

Bone mass density and associated factors in cystic fibrosis patients of young age

Aim: To investigate bone mineral status in young cystic fibrosis (CF) patients and determine risk factors related with the development of low bone mineral density (BMD). Methods: We determined, in 81 patients with CF, 4 to 23-years-old, BMD as well as factors, which are thought to play a role in the development of reduced BMD. Results: BMD Z-score was between -1 and -2.5 in 27 (33%) and lower than -2.5 in 9 (11%). Means of BMD Z-score were lower than the expected value of 0 in the three groups of children, adolescents and young adults (P = 0.004; P &lt; 0.001; P = 0.048, respectively), but they did not differ among them (P = 0.114). Analysis showed that Shwachman-Kulczycki (SK) score, gender and levels of 25-hydroxy- vitamin D were significant predictors of BMD Z-score. Significant also was the interaction between gender and SK score. Conclusions: Our study supports that BMD may be reduced from a young age in CF patients though this needs to be confirmed using true volumetric measures of BMD. This defect is related to disease severity with males being more vulnerable. Inefficient levels of vitamin D are very common and contribute significantly to impaired bone health. The latter finding underlines the need for higher supplementation doses

Vascular Endothelial Growth Factor Inhibitors for Treatment of Corneal Neovascularization: A Meta-Analysis

Purpose: To evaluate the therapeutic effect of bevacizumab (Avastin) on corneal neovascularization (NV). Methods: Systematic review and meta-analysis of the literature was performed. Seven eligible clinical human studies and 18 eligible experimental animal studies examining the effectiveness of bevacizumab treatment on corneal NV were included in the meta-analysis. Pertinent publications were identified through a systematic search of PubMed. All references of relevant reviews and eligible articles were also screened, and data were extracted from each eligible study. The random-effects model (of DerSimonian and Laird) was used to combine the results from the selected studies. Heterogeneity was explored using available data. Publication bias was also assessed. Results: A significant reduction of corneal neovascularized area was seen in clinical human studies, with a pooled reduction of 36% [95% confidence interval (CI), 18%-54%] overall, of 32% (95% CI, 10%-54%) for subconjunctival anti-vascular endothelial growth factor injections, and 48% (95% CI, 32%-65%) for topical treatment. Pooled mean change in best-corrected visual acuity showed an improvement in best-corrected visual acuity by 0.04. The summary standardized mean difference in animal studies indicated a statistically significant reduction in the area of corneal NV when treated with bevacizumab compared with the control group by -1.71 (95% CI, -2.12 to -1.30). The subtotal pooled standardized mean differences were -1.83 (95% CI, -2.38 to -1.28) for subconjunctival anti-vascular endothelial growth factor injections and -1.50 (95% CI, -1.88 to -1.12) for topical treatment. Conclusion: Our results suggest that both topical and subconjunctival bevacizumab achieve significant reduction in the area of corneal NV. This meta-analysis provides an evidential basis for the new therapeutic concept of treating corneal NV with antiangiogenic therapy

Reliability and validity of the KIDSCREEN-52 health-related quality of life questionnaire in a Greek adolescent population

Background: The KIDSCREEN-52 is a worldwide instrument for measuring health-related quality of life (HRQoL) in children and adolescents. The aim of this study is to assess reliability and validity of the Greek version of KIDSCREEN. Methods: Questionnaires were collected from a representative nationwide sample of 1,194 adolescents aged from 11 to 17 years. Internal consistency reliability was determined by calculation of the Cronbach alpha coefficient. A confirmatory factor analysis (CFA) was conducted in order to test the construct validity of the questionnaire. Validity was further examined by investigating the correlation of KIDSCREEN with the Strengths and Difficulties Questionnaire (SDQ) and its association with socioeconomic and health-related factors. Results: Internal consistency reliability was accepted with a Cronbach alpha above 0.73 for all KIDSCREEN dimensions. CFA showed that the ten-dimensional model fitted the data well (root mean square error of approximation (RMSEA) = 0.048, comparative fit index (CFI) = 0.971 and goodness of fit index (GFI) = 0.965). Correlation coefficients between KIDSCREEN and SDQ dimensions were significant. Adolescents of low socioeconomic status reported lower scores in the majority of KIDSCREEN dimensions. Also, adolescents with chronic health problem had poorer quality of life concerning physical well-being and other dimensions of KIDSCREEN. Conclusions: The Greek version of KIDSCREEN-52 was found to have satisfied psychometric properties and could be suitable for assessing HRQoL in Greek adolescents