in interventional or observational longitudinal studies, the issue of missing values is one of the main concepts that should be investigated. the researcher's main concerns are the impact of missing data on the final results of the study and the appropriate methods that missing values should be handled. regarding the role and the scale of the variable that missing values have been occurred and ...

in many area of medical research, a relation analysis between one response variable and some explanatory variables is desirable. regression is the most common tool in this situation. if we have some assumptions for such normality for response variable, we could use it. in this paper we propose a nonparametric regression that does not have normality assumption for response variable and we focus ...

background: the present study was performed to develop a scoring system for predicting cure status in patients with cutaneous leishmaniasis (cl). materials and methods: this study included 199 patients with cl from skin diseases and leishmaniasis research center (isfahan, iran). data were collected as longitudinal in each visit of patients. we applied ordinal logistic generalized estimating equ...

In many area of medical research, a relation analysis between one response variable and some explanatory variables is desirable. Regression is the most common tool in this situation. If we have some assumptions for such normality for response variable, we could use it. In this paper we propose a nonparametric regression that does not have normality assumption for response variable and we focus ...

Mixed models are widely used to analyze longitudinal data. In their conventional formulation as linear mixed models (LMMs) and generalized LMMs (GLMMs), a commonly indispensable assumption in settings involving longitudinal non-Gaussian data is that the longitudinal observations from subjects are conditionally independent, given subject-specific random effects. Although conventional Gaussian...

each semester, students are asked to evaluate the academic staff through an online questionnaire. generalized estimating equations model (gee), taking into account the correlation between scores, is the established tool to analyze longitudinal data. the aim of this manuscript is to identify characteristics that influence staff score and to address the importance of selection of appropriate corr...

background: growth failure in children less than five years old can lead to the serious complications such as increased mortality, learning difficulties or physical disability. the aim of this study was to investigate the non-organic factors affecting the growth trend in less than two years children living in zanjan, iran.   methods: this longitudinal study was conducted on a sample of 3566 chi...

a generalized heckman model is used for the joint modeling of longitudinal continuousresponses and dropout in order to see the influence of a small perturbation of the elements of thecovariance structure on displacement of the likelihood. the perturbation from random dropout in thedirection of informative dropout is considered for mastitis data.

The ONS Longitudinal Study (LS) includes information from the 1971, 1981, 1991 and 2011 censuses. This article explains definitional differences over time, and their implications for household and family classifications.List of tables, 65.