Background: Missing values in data are found in a large number of studies in the field of medical sciences, especially longitudinal ones, in which repeated measurements are taken from each person during the study. In this regard, several statistical endeavors have been performed on the concepts, issues, and theoretical methods during the past few decades.

Methods: Herein, we focused on the missing data related to patients excluded from longitudinal studies. To this end, two statistical parameters of similarity and correlation coefficient were employed. In addition, metaheuristic algorithms were applied to achieve an optimal solution. The selected metaheuristic algorithm, which has a great search functionality, was the Cuckoo search algorithm.

Results: Profiles of subjects with cervical dystonia (CD) were used to evaluate the proposed model after applying missingness. It was concluded that the algorithm used in this study had a higher accuracy (98.48%), compared with similar approaches.

Conclusion: Concomitant use of similar parameters and correlation coefficients led to a significant increase in accuracy of missing data imputation.


Keywords: Missing data, Imputation of missing data, Cuckoo algorithm, Longitudinal data
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October-December 2019 (Volume 11, Issue 4)


The 6th World Conference on Research Integrity (WCRI) is to be held on June 2-5, 2019 in Hong Kong.

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