Evaluating competing models of distress tolerance via structural equation modeling.

Distress Tolerance (DT) is a transdiagnostic risk and maintenance factor implicated in a wide range of internalizing spectrum (INT) disorders. DT is commonly conceptualized as a higher-order construct, yet its lower-order dimensions are still debated. While the tolerance of negative emotions, frustration, and physical discomfort are widely considered to be central features of DT, the inclusions of intolerance of uncertainty (IU) and anxiety sensitivity (AS) are disputed. This study is the first to compare the two leading hierarchical models of DT directly. We also propose and test a DT model which includes IU and AS as lower-order dimensions. This "combined" model drew from the prior hierarchical theories and subsequent research demonstrating IU and AS to be highly correlated. To evaluate the competing models of DT, structured equation modeling was used to construct latent models representing each leading model and our novel "combined" model. A clinical sample was analyzed (N = 278), with participants having completed self-report scales measuring DT's theorized lower-order dimensions. Of the proposed models, the "combined" model demonstrated the best fit indices in the context of INT. A regression model with our "combined" model indicated that even after its shared variance with the Distress Intolerance Index (DII) was removed, it still had a moderate association with INT (β = 0.805, p < .01). This suggests that the only extant measure of the higher-order DT construct, the DII, fails to capture considerable variance in its latent structure. Future directions are discussed.