Table 2.
Means, standard deviations, reliabilities, and intercorrelations of symptoms based on traditional average scores and two-part models
| Traditional model | Two-part model | |||
|---|---|---|---|---|
| Composite score | Frequency | Intensity | Frequency with intensity a |
|
| Pain | ||||
| Mean | 0.90 | 29.7% | 2.03 | |
| SD | 0.93 | 6.3% –68.0% b | 1.51 | |
| Reliability | .89 | .85 | .91 | |
| Correlation | .60 | |||
| Tired | ||||
| Mean | 2.25 | 68.5% | 3.10 | |
| SD | 1.43 | 30.2% –93.1% b | 1.09 | |
| Reliability | .77 | .73 | .76 | |
| Correlation | .41 | |||
| Stress | ||||
| Mean | 1.35 | 46.8% | 2.50 | |
| SD | 1.30 | 14.0% –82.1% b | 1.14 | |
| Reliability | .77 | .74 | .77 | |
| Correlation | .48 | |||
| Sad | ||||
| Mean | 0.62 | 22.8% | 2.15 | |
| SD | 1.05 | 4.0% –60.1% b | 1.31 | |
| Reliability | .80 | .78 | .84 | |
| Correlation | .39 | |||
Note: N = 12,829.
a
Correlations are adjusted for unreliability.
b
Values are −1SD and +1SD around the mean frequency.