How well does the CWEQ II measure structural empowerment? : findings from applying Item Response Theory

The main purpose of this paper is to examine the psychometric properties of the original five-point CWEQ II using Item Response Theory (IRT) methods, followed by an examination of the revised three-point CWEQ II. (1) Background: The psychometric properties of the CWEQ II have not been previously assessed using more robust techniques such as IRT. (2) Methods: This is a secondary analysis of baseline data from 1067 staff nurses whose leaders had attended a leadership development program. Data were analyzed using a polytomous IRT model. (3) Results: The two versions of CWEQ II fit the SE data equally as each had only one poor-fitting item. For the five-point CWEQ II, discriminant ability was poor for a majority of the items; one item demonstrated a disordinal step difficulty parameter; and item reliability was supported for a relatively wider range of SE levels. The discriminant ability and reliability of items for the three-point CWEQ II was better than those of the five-point CWEQ II, but for a narrower range of SE levels; and the disordinal step difficulty parameter was resolved. (4) Conclusion: The appropriate use of each version of the scale depends on the conditions of the work setting targeted.