Validation and comparative assessment of low anterior resection syndrome questionnaires in Greek rectal cancer patients.

BACKGROUND: Our study validated the low anterior resection syndrome (LARS) score questionnaire, the colorectal functional outcome (COREFO) questionnaire, and the Memorial Sloan-Kettering Cancer Center bowel function instrument (MSKCC-BFI) in Greek rectal cancer patients. METHODS: Internal consistency, repeatability, construct and discriminant validity were evaluated for LARS, COREFO, and MSKCC-BFI questionnaires. The convergent validity was assessed by correlations with the European Organization for Research and Treatment of Cancer (EORTC) QLQ-C30 and QLQ-CR29 domains. RESULTS: The internal consistency of the questionnaire's subscales was satisfactory (Cronbach's a>0.6). The repeatability test showed extremely high reproducibility (intraclass correlation coefficient >0.9). High positive correlation was detected between the 3 questionnaires' total scores and each of their questions (rho>0.5), indicating their valid construction. All questionnaires demonstrated a good convergent validity through correlations with comparable domains of the EORTC QLQ-C30 and CR29. Statistically significant associations were detected between LARS, COREFO, MSKCC-BFI scores and tumor distance and temporary stoma (P<0.001 and P=0.009, P<0.001 and P=0.005, P<0.001 and P=0.002 respectively). In addition, COREFO and MSKCC-BFI scores were significantly associated with radiation therapy. LARS score was significantly correlated to all COREFO and MSKCC-BFI subscales. CONCLUSIONS: The Greek versions of the LARS score, COREFO and MSKCC-BFI questionnaires were proven to have good psychometric properties and can be used as specific and valid instruments for measuring LARS. Since the COREFO and MSKCC-BFI questionnaires, which are more extensive and possibly less applicable in routine clinical practice, showed no advantages in relation to the LARS score, the latter may be established as the simplest, fastest to complete and most targeted tool for assessing LARS.

Can Mediterranean diet really influence obesity? Evidence from propensity score matching.

Worldwide obesity rates have stimulated interest in healthy dietary patterns. One well-known dietary pattern is the Mediterranean diet, which has been linked with several beneficial health effects. However, concerns have also been raised regarding the Mediterranean diet's role in promoting weight gain. We explored the effect of the Mediterranean diet on body mass index using the propensity score matching approach. We found no statistically significant average treatment effect on the treated and therefore cannot confirm that a causal link exists between Mediterranean diet and body mass index.

A theoretical and empirical investigation of nutritional label use.

Due in part to increasing diet-related health problems caused, among others, by obesity, nutritional labelling has been considered important, mainly because it can provide consumers with information that can be used to make informed and healthier food choices. Several studies have focused on the empirical perspective of nutritional label use. None of these studies, however, have focused on developing a theoretical economic model that would adequately describe nutritional label use based on a utility theoretic framework. We attempt to fill this void by developing a simple theoretical model of nutritional label use, incorporating the time a consumer spends reading labels as part of the food choice process. The demand equations of the model are then empirically tested. Results suggest the significant role of several variables that flow directly from the model which, to our knowledge, have not been used in any previous empirical work.