Choosing appropriate imputation methods for missing data : a decision algorithm on methods for missing data

الملخص EN

Missing values commonly happen in the realm of medical research, which is regarded creating a lot of bias in case it is neglected with poor handling.

However, while dealing with such challenges, some standard statistical methods have been already developed and available, yet no credible method is available so far to infer credible estimates.

The existing data size gets lowered, apart from a decrease in efficiency happens when missing values is found in a dataset.

A number of imputation methods have addressed such challenges in early scholarly works for handling missing values.

Some of the regular methods include complete case method, mean imputation method, Last Observation Carried Forward (LOCF) method, Expectation-Maximization (EM) algorithm, and Markov Chain Monte Carlo (MCMC), Mean Imputation (Mean), Hot Deck (HOT), Regression Imputation (Regress), K-nearest neighbor (KNN),K-Mean Clustering, Fuzzy K-Mean Clustering, Support Vector Machine, and Multiple Imputation (MI) method.

In the present paper, a simulation study is attempted for carrying out an investigative exploration into the efficacy of the above mentioned archetypal imputation methods along with longitudinal data setting under missing completely at random (MCAR).

We took out missingness from three cases in a block having low missingness of 5% as well as higher levels at 30% and 50%.

With this simulation study, we concluded LOCF method having more bias than the other methods in most of the situations after carrying out a comparison through simulation study.