↵^a Only significant terms are reported.

^b CAT=Computerized Adaptive Test, pain observed=pain intensity change score was missing (ie, 0) vs pain intensity change score was reported (ie, 1), pain change observed=(pain intensity change score) × (pain observed), age group=18–44 years vs 45–64 years vs 65 years and older, duration of condition=acute (0–21 days) vs subacute (22–90 days) vs chronic (≥91 days), fear=low vs elevated fear-avoidance beliefs.

^c Inference of GLM regression parameters was performed using the Wald test statistic where the estimated parameter was compared with a chi-square distribution. The null hypothesis was no significant effect on change in function for a continuous variable and no significant difference in change in function between groups for a categorical variable.