Figure 2.
Strength of predictor variables in the multivariable model for pain impact. The relative importance of each predictor variable in the multivariable regression model for pain impact determined by Wald Chi-square (X2) test. X-axis is represented as Wald chi-square (X2) minus degrees of freedom (df), which indicates the strength of the predictor variable’s impact on the outcome (ie, pain impact) and its explanatory power in the model. A larger X2 − df value suggests the predictor variable has a stronger impact on the outcome and provides more explanatory power to the model. Corresponding P-values < .05, indicates that predictor variable contributes significantly to model. P-values > .05 indicates predictor variable does not significantly contribute the model, that is, the variable could be omitted without a meaningful or significant effect on the model. N = 657; R2 = .60, .