@article{article_377421, title={Use of Generalized Estimating Equations with Multiple Imputations for Missing Longitudinal Data}, journal={Yüzüncü Yıl Üniversitesi Fen Bilimleri Enstitüsü Dergisi}, volume={23}, pages={96–103}, year={2018}, url={https://izlik.org/JA76BB54ZS}, author={Ser, Gazel and Okut, Hayrettin}, keywords={Marjinal modeler,Çalışma korelasyon,Çoklu atama}, abstract={<p class="MsoNormal" style="margin:0cm;margin-bottom:.0001pt;text-indent:0cm;line-height:normal;"> <span lang="en-us" style="font-size:10pt;font-family:’Times New Roman’, serif;" xml:lang="en-us">This study aimed to assess the performance of multiple imputation for the Generalized Estimating Equation (GEE) method, one of the marginal model approaches. Observations with longitudinal data structure obtained from 1044 individuals during five years were used. Smoking frequency, response variable with Poisson distribution and the independent variables thought likely to affect these were taken into consideration. These variables are the individual’s alcohol use frequency, the score for friend influence on the individual’s smoking, the score for individual’s listening to his/her family, individual-family relationship score, marriage status of parents, gender and age. Four different working correlation structures were examined to determine the study correlation structure in GEE. Quasi information criterion was used to determine the most appropriate working correlation structure to fit the data. In estimating the missing observation, the missing observations were assumed to be missing at random, and missing observations were estimated using multiple imputation (MI). Thus, the GEE method was applied again to the complete data set obtained and MI-GEE results were obtained. As a result, the appropriate working correlation structure for GEE and MI-GEE was determined as the independent structure, and parameter estimations were obtained using this structure. In both cases, empirical standard error results were evaluated. Accordingly, in the data set with missing observations, effect of alcohol use and family relationship status (p<0.001) and of age (p<0.01) on smoking was found to be significant in GEE results. In the MI-GEE results, effect of alcohol use, family relationship score, gender, age (P<0.001) and the score for the individual’s relationship with his/her family (p<0.01) was found to be significant. Standard error estimations obtained for MI-GEE were much smaller compared to the data with missing observations. </span> </p> <p> </p> <p> </p> <p class="MsoNormal" style="margin:0cm;margin-bottom:.0001pt;text-indent:0cm;line-height:normal;"> <b> <span lang="en-us" style="font-size:10pt;font-family:’Times New Roman’, serif;" xml:lang="en-us"> </span> </b> </p> <p> <b>  </b> </p> <b> </b>}, number={1}