Likert-based vs. semantic differential-based scorings of positive psychological constructs: A psychometric comparison of two versions of a scale measuring resilience

In measuring positive psychological constructs, Likert-based response formats may introduce an acquiescence bias. To reduce this, items usually are transformed into negations of the concept. Such transformations may introduce errors, as negations of positive constructs may appear contra-intuitive. A semantic differential response format may be an alternative to negations for reducing the acquiescence bias. A drawback with this format is the increased cognitive demand, hence introducing new errors in scores. Using a scale measuring resilience as an example of a positive psychological construct, this study compared a Likert and a Semantic differential response format with respect to psychometric properties. Both formats were completed by 334 university students. Apart from slightly reduced variance and internal consistency, the factor structure in the semantic differential version fitted the data better, indicating better properties in terms of uni-dimensional loading items. Systematic error variance related to negative and positive differentials was minor (3.9%). In conclusion, in measuring positive psychological constructs, a semantic differential format may effectively reduce acquiescence bias without lowering psychometric quality.