Predictability is the degree to which a correct prediction or forecast of a system's state can be made either qualitatively or quantitatively. Predictability of a predictor depends whether
(1) criterion chosen for the study is appropriate and meets the standards for reliability and validity,
(2) processes used by the investigators to assess both model efficiency and accuracy are appropriate,
3) predictors selected for use in the model are reasonable based on theory or previous research, and
4) assessing model stability through a process of cross-validation,