The internal consistencies of the 1987 SEI maturity questionnaire and the SPICE capability dimension

This paper presents the results of an empirical evaluation of the reliability of two commonly used assessment instruments: the 1987 SEI maturity questionnaire and the SPICE v1 capability dimension. The type of reliability that was evaluated is internal consistency. A study of the internal consistency of the 1987 questionnaire was only briefly mentioned in a 1991 article, and the internal consistency of the SPICE v1 capability dimension has not been evaluated thus far. We used two different data sets to evaluate the internal consistency of each instrument. Our results indicate that both assessment instruments are very reliable and also have similar reliability levels. The results are encouraging for users of assessment instruments, and provide a baseline with which to compare subsequent versions of these instruments.