Psychometrics in Counselling Practice
Using Rasch models as a basis for further development of questionnaires for personality diagnosis
Contribution to the practice of diagnostics
At the ZHAW School of Psychology and IAP Institute of Applied Psychology, diverse psychometric questionnaires are used in various fields of practice. Since September 2012, evidence-based diagnostic instruments have been made available to the world of practice by the Plattform Laufbahndiagnostik. The questionnaires are used in consultations and in continuing education courses at the IAP as well as in degree programmes at the School of Psychology. They are freely accessible and thus available at no cost to other counselling services.
The platform is under continuous further development. The emphasis in further development is on the practical utility of the instruments. The aim is to make theoretically based, scientifically tested instruments available to the world of practice. Consideration is given to both new developments in personality psychology and state-of-the-art in psychometrics (especially probabilistic test theory (PTT), Rasch models). Further development is being undertaken in the context of collaboration between the ZHAW School of Psychology and the ZHAW School of Engineering. In a preliminary project, two questionnaires on the platform were already tested and further developed: Fragebogen zur Erfassung der Karriereorientierungen (KO) (Career Anchors; see Schein & van Maanen, 2013; Schein, 1975) and Fragebogen zur Erfassung der Persönlichkeit (MRS-30; see Schallberger & Venetz, 1999). The analyses found that the factor structure of the two questionnaires can be replicated quite well. The Rasch models including DIF analyses yielded promising results. But it also became clear that with regard to the factor structure as well as with regard to fit, according to the Rasch model there is a need for further development of both questionnaires. Based on the results of the preliminary project, the questionnaires were substantially further developed and updated on the platform at the end of July 2015.
In the spring of 2016 the two questionnaires and other questionnaires will be tested and further developed. The aim of the research project is to make a contribution to the practice of diagnosis. Specifically, the aims are as follows:
- Contribute to the practice of diagnosis in the context of counselling: Based on specific questionnaires, the aim is to develop and establish a procedure for optimizing questionnaires. The basis will be probabilistic test theory (PTT) (Rasch models as a basis for further development of questionnaires).
- Test and publish a newly developed model test and fit statistics for Rasch scaling on large data sets
- Include and test up-to-date developments in personality psychology
Funded by Biäsch Foundation