TY - JOUR T1 - Determining factors affecting fasting blood sugar in patients with type 2 diabetes using Copula functions TT - تعیین عوامل موثر بر قند خون ناشتای بیماران مبتلا به دیابت نوع دو در طول زمان با به کارگیری توابع مفصل JF - RJMS JO - RJMS VL - 21 IS - 122 UR - http://rjms.iums.ac.ir/article-1-3278-en.html Y1 - 2014 SP - 1 EP - 8 KW - Copula functions KW - Fasting blood sugar KW - Longitudinal data N2 - Background: The defining characteristic of a longitudinal study is that subjects are measured repeatedly through time. Longitudinal studies are in contrast to cross-sectional studies, in which a single outcome is measured for each individual. The primary objective of this study is to use copulas to model the within-subject dependencies over time. Methods: In this longitudinal study, we used the hospital records of patients with type 2 diabetes in Lolagar hospital, Tehran. Information of patients who visited the hospital at least twice during the years 2006-11 were recorded. Factors affecting fasting blood sugar were determined by regression model and the use of copula functions. We used the Residuals pp plot of copula function for selecting copula. Fitting model was done with R software. Results: In this study, only three explanatory variables were statistically significant. Smoking (p M3 ER -