Differences between Cronbach’s alpha coefficients, with small samples and parts: A VB program

César Merino-Soto


This paper presenting a computer program written in VB 6.0, to calculate the difference between internal consistency coefficients (Cronbach’s alpha) obtained in independent small samples and with instruments have a small number of parts or items. The comparison of reliability coefficients allow to identify possible differences in amount of measurement error in instruments; this methodology use the hypothesis testing approach for test the null hypothesis of equally reliability coefficients. This situation is tending to be common in clinical practice between psychologists or allied career, and even in the construction phases of instruments of measurement, for example in pilot samples. The proposed technique is from the work of Feldt and Kim (2006), and offers a viable and interesting methodological proposal that expands the analysis of the reliability of instruments of psychological and educational measurement.


reliability; software; methodology; psychometry; Cronbach’s alpha.

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DOI: http://dx.doi.org/10.6018/analesps.32.2.203841


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