Technical Data

The reliability of the ELTiS test forms was estimated using Cronbach’s coefficient alpha. The values of coefficient alpha range from 0 to 1, with 1 indicating that the test scores are entirely free from random measurement error and 0 indicating that they are entirely determined by it. Coefficients of 0.8 and above are essential for wide-scale assessments, while coefficients of 0.9 and above are highly desirable. Reliability increases with test length. As a result, the total test scores should be used for decision-making based on the ELTiS test.

The table below lists the coefficient alpha statistics for ELTiS Forms 1 and 2. For further discussion of these and other statistical characteristics of the ELTiS forms, please refer to the ELTiS Technical Supplement, available upon further request from Ballard & Tighe.

 

Listening Reading Total Test
ELTiS Form 1 .82 (N=18098) .86 (N=17989) .91 (N=17709)
ELTiS Form 2 .76 (N=17196) .84 (N=17229) .89 (N=17144)