What is the percentage of missing item scores within subjects?

Longitudinal analysis > Missings in predictor/covariate > MNAR > <50% missing data

How many item scores do subjects have missing? Subjects that have less than 75% of the item scores of a multi-item questionnaire missing are considered to have missing item score data. However, subjects that have more than 75% of the item scores missing are considered to have the entire questionnaire missing, i.e., missing total scores for that questionnaire.