Form equivalence of the speech perception in noise (SPIN) test

An evaluation was conducted of the equivalence of the ten forms of the Speech Perception in Noise (SPIN) Test with normal hearing subjects. Each subject was tested monaurally on all ten forms. Twenty-five subjects were presented the materials at 80 dB SPL at a signal-to-babble ratio of - 1 dB. An additional 25 subjects heard the materials at 30 dB SPL, at a signal-to-babble ratio of + 3 dB. The data were analyzed for equivalence using a parallel tests model. A detailed rationale for the application of this model to the equivalence of the SPIN test is presented. The results indicated that a subset of seven lists fits the equivalence model for PH, PL, and difference (PH - PL) scores. Additionally, analysis of list-pair data (combination of companion forms) suggested that all five list-pairs resulted in equivalent performance.