TABLE 3.
Summary of imputation methods for mixed-type longitudinal data
| Approach | Data format | Method | Imputation models | |
|---|---|---|---|---|
| FCS | Imputation model for binary variables | Imputation model for count variables | ||
| Wide | FCS-Standard (LM) | Logistic regression | Linear regression | |
| FCS-Standard (PMM) | Logistic regression | Predictive mean matching | ||
| FCS-Standard (Poisson) | Logistic regression | Poisson regression | ||
| Long | FCS-LMM-latent | Multilevel linear regression on latent variables | Multilevel linear regression | |
| FCS-GLMM (Gaussian) | Multilevel logistic regression | Multilevel linear regression | ||
| FCS-GLMM (Poisson) | Multilevel logistic regression | Multilevel Poisson regression | ||
| JM | Wide | JM-GL | General location model | |
| Long | JM-MLMM-latent (common) | Multivariate multilevel linear model with latent variables and homoscedastic within-subject variance | ||
| JM-MLMM-latent (random) | Multivariate multilevel linear model with latent variables and heteroscedastic within-subject variance | |||
| JM-MGLMM | Multivariate multilevel generalized linear model using a logit and log link for binary, count variables | |||