Variance in functioning (functional health status measured by COOP/WONCA) over the 4 measurement periods (T1-T4) were significantly predicted by experience of traumas in childhood (B SE) =.50(.24), β =.29*), high levels of pain intensity (B SE) =.02(.00), β =.42**) and pain experience (B SE) =.02(.00), β =.37*), and poor psychological capacity (B SE) =.05(.02), β = -.68*) at baseline (T1).
Moreover, poor physiological capacity (B SE) = -.02(.00), β = -.44**) and high levels of anxiety (B SE) =.13(.04), β =.48**) and depression (B SE) =.16(.04), β =.58***) at the end of the rehabilitation program (T3) were found to significantly predict the variance in functioning (functional health status measured by COOP/WONCA) over the 4 measurement periods.
Regression analysis showed that success at living according to values predicted variance in functioning independent of acceptance of pain, supporting its incremental utility in a contextual analysis of chronic pain and its potential importance in treatment for chronic pain.
In fact, employment status was one of the strong predictors of variance in functioning for two scales: the 'social roles and mobility' and the 'minor self-care limitations' index.
High levels of pain intensity (β =.42**) and pain experience (β =.37*), and poor psychological capacity (β = -.68*) at baseline, as well as poor physiological capacity (β = -.44**) and high levels of anxiety (β =.48**) and depression (β =.58***) at the end of the rehabilitation program were the most important prognostic factors of variance in functioning over the 4 measurement periods.
Figure 4 Noise variance estimation in function of the number of iterations and comparison with the perfect case.
A large, significant component of the effect was direct from DUP to social function score, accounting for 78% of the explained variance in social function in this model (r= 0.19, P=0.04).
Results showed that a large component (39% of the explained variance in social function) of the effect was a direct effect of DUP on social function, although this did not achieve statistical significance (P=0.11).
This resulted in the pathway from DUP to social function via negative syndrome being significant, accounting for 59% of the explained variance in social function (r= 0.16, P=0.02) (Fig. 1).
This possibility is supported by the observation (consonant with Barkley's theory) that the activity severity composite correlated strongly with multiple domains of impaired executive function on the Brown ADD Scale, and explained about four-fold more of the variance in executive function ratings than either of the attention composites.
