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Missing data is a commonly encountered problem in longitudinal research. Methodological articles provide advice on ways to handle missing data at the analysis stage, however, there is less guidance for researchers who wish to use supplemental samples (i.e., the addition of new participants to the original sample after missing data appear at the second or later measurement occasions) to handle attrition...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.