Confirmatory factor analysis of the irrational Performance Beliefs Inventory (iPBI) in a sample of amateur and semi-professional athletes

Objectives. This investigation sought to test the construct validity of the irrational
performance beliefs inventory (iPBI) in a sample of amateur and semi-professional
athletes.
Method. In total, 550 athletes (312 men, 212 women, Mage = 38.04 ± 13.80 years)
completed the iPBI and demographic questions at a single time point.
Results. Confirmatory factor analysis showed lower than acceptable fit indices for the
28-item iPBI (comparative fit index [CFI] = .84). After removal of potential problem
items, a 20-item version (iPBI-2) was developed (CFI = .91). Results showed that
amateur athletes scored higher than semi-professional athletes on primary irrational
beliefs and low frustration tolerance, whereas semi-professional athletes scored higher
than amateur athletes on depreciation.
Conclusions. This study provides initial evidence of construct validity for a 20-item
version of the iPBI in an athletic sample, and shows medium effect size differences in
irrational beliefs between amateur and semi-professional athletes.