Stratification allows to control for confounding by creating two or more categories or subgroups in which the confounding variable either does not vary or does not vary very much. The Mantel-Haenszel formula is applied in cohort and in case-control studies to calculate an overall, unconfounded, effect estimate of a given exposure for a specific outcome by combining stratum-specific relative ris...

OBJECTIVE To define the prevalence of overweight and obesity among school-aged children resident in mountain areas, rural areas and urban areas. DESIGN, SETTING AND SUBJECTS The sample (n = 12832; 50.7% boys) included 9- and 11-year-old children of the Veneto Region of north-east Italy. Overweight and obesity status were determined using the International Obesity Task Force cut-off points for...

This study aims to determine whether the items in PISA 2018 Mathematical Literacy test show differential item functioning (DIF) according gender and parental education level. The sample of consisted a total 521 students who participated practice Turkey answered booklets numbered 1 7. research was conducted on 45 these booklets. Before proceeding DIF analysis, data were examined terms missing va...

This paper reviews approximate confidence intervals for some effect parameters common in cancer epidemiology. These methods have computational feasibility and give nearly nominal coverage rates. In the analysis of crude data, the simplest type of epidemiologic analysis, parameters of interest are the odds ratio in case-control studies and the rate ratio and difference in cohort studies. These p...

This study was to use differential item functioning (DIF) analysis to examine if there were items in the Mental, Emotional, and Bodily Toughness Inventory (MeBTough) functioning differently across gender and athletic membership. A total of 444 male (56.3%) and female (43.7%) participants (30.9% athletes and 69.1% non-athletes) responded to the MeBTough items. Using Mantel-Haenszel and SIBTEST m...