The second research question, addressing whether characteristics of the FC (i.e., personal, environmental, health/illness, symptoms) as well as of the patient (i.e., personal, disease, symptoms) influenced the trajectories of evening and morning fatigue in FCs, was tested in the Level 2 analyses. Exploratory analyses were completed with all of the potential predictor variables listed in Table 3. To improve estimation efficiency and construct models that were parsimonious, exploratory Level 2 analyses were done in which each potential predictor was assessed to see if it would result in a better fitting model if it alone was added as a Level 2 predictor. Predictors with a t-value of < 2.0 were dropped from subsequent model testing. All of the significant predictors from these exploratory analyses were entered into the models to predict each individual change parameter (i.e., intercepts and/or slopes). Only those predictors that maintained a significant contribution in conjunction with other variables were retained in the final models of evening and morning fatigue in FCs.