title: Determining Sufficient Number of Imputations Using Variance of Imputation Variances: Data from 2012 NAMCS Physician Workflow Mail Survey.
abstract: How many imputations are sufficient in multiple imputations? The answer given by different researchers varies from as few as 2 - 3 to as many as hundreds. Perhaps no single number of imputations would fit all situations. In this study,η, the minimally sufficient number of imputations, was determined based on the relationship betweenm, the number of imputations, andω, the standard error of imputation variances using the 2012 National Ambulatory Medical Care Survey (NAMCS) Physician Workflow mail survey. Five variables of various value ranges, variances, and missing data percentages were tested. For all variables tested,ωdecreased asmincreased. Themvalue above which the cost of further increase inmwould outweigh the benefit of reducingωwas recognized as theη. This method has a potential to be used by anyone to determineηthat fits his or her own data situation.
authors.affiliation: National Center for Health Statistics, Centers for Disease Control and Prevention, Hyattsville, MD, USA.
authors.forename: Qiyuan
authors.initials: Q
authors.lastname: Pan
authors.affiliation: National Center for Health Statistics, Centers for Disease Control and Prevention, Hyattsville, MD, USA.
authors.forename: Rong
authors.initials: R
authors.lastname: Wei
authors.affiliation: National Center for Health Statistics, Centers for Disease Control and Prevention, Hyattsville, MD, USA.
authors.forename: Iris
authors.initials: I
authors.lastname: Shimizu
authors.affiliation: National Center for Health Statistics, Centers for Disease Control and Prevention, Hyattsville, MD, USA.
authors.forename: Eric
authors.initials: E
authors.lastname: Jamoom
keywords: Hot-Deck Imputation; Multiple Imputation; Sufficient Number of Imputations