Preliminary Psychometric Scale Development Using the Mixed Methods Delphi Technique

This study implemented a Delphi Method, a systematic technique which relies on a panel of experts to achieve consensus, to evaluate which questionnaire items would be the most relevant for developing a new Propensity to Trust scale. Two surveys were administered to academic lecturers, professors and Ph.D. candidates specialising in the fields of either individual differences, human robot interaction, or occupational psychology. Results from 28 experts produced 33 final questionnaire items that were deemed relevant for evaluating trust. We discuss the importance of content validity when implementing scales, while we also emphasise the need for more documented scale development processes in psychology. Furthermore, we propose that the Delphi approach could be utilised as an effective and economical method for achieving content validity while also providing more transparency of a scale’s creation.