Table 2.
Results of multilevel models examining the association between preceding symptoms—pain, fatigue, depressed mood, and cognitive function—and subsequent physical activity, controlling for age, MS subtype, upper- and lower-extremity functioning, and average of EMA symptom ratings
| Fixed effects | |||
|---|---|---|---|
| Physical activity (average activity counts/minute) | |||
| B | SE | p | |
| Between-person predictor variables (time invariant) df = 96 | |||
| Intercept | 338.07 | 53.24 | <.0001 |
| Age | −3.15 | 0.75 | <.0001 |
| MS type | 8.86 | 18.18 | .63 |
| UE functioning | −0.26 | 0.80 | .75 |
| LE functioning | −0.03 | 0.98 | .98 |
| Avg. pain | 6.01 | 6.01 | .31 |
| Avg. fatigue | −3.04 | 6.76 | .65 |
| Avg. depressed | −0.16 | 4.94 | .97 |
| Avg. cognitive | 4.53 | 5.42 | .41 |
| Within-person predictor variables—Symptom ratings (preceding activity) df = 2,080 | |||
| Δ Pain | 0.32 | 2.20 | .89 |
| Δ Fatigue | −5.40 | 1.54 | .0005 |
| Δ Depressed | −5.92 | 2.03 | .004 |
| Δ Cognitive | 0.94 | 1.71 | .58 |
| Between-person R-squared (all symptoms combined) = 0.036 | |||
| Within-person R-squared (all symptoms combined) = 0.126 | |||
B unstandardized beta; SE standard error; Δ person-centered variable representing momentary deviation (change) from a person’s average.
An (AR1) autoregressive matrix was used to model the error variance; Intercept and momentary pain, fatigue, and cognitive function were included as random effects; MS type relapsing remitting MS subtype, progressive subtypes was reference category; LE lower extremity; UE upper extremity; Avg. person-average of EMA symptom ratings during home monitoring period.