Psychometric Properties of the Second Version of the Occupational Performance History Interview (OPHI-II)

Objective. This study examined the validity of the Occupational Identity, Occupational Competency, and Occupational Behavior Settings scales of the second version of the Occupational Performance History Interview (OPHI-II). The study also asked whether the scales' items were targeted to and could effectively discriminate between persons at different levels of adaptation. Method. Data were collected from 151 raters on 249 subjects from eight countries and in six languages. Many-faceted Rasch analysis was used to analyze the data. Results. The items of each scale worked effectively to measure the underlying construct for which they were designed. All three scales validly measured more than 90% of the subjects, who varied by nationality, culture, age, and diagnostic status. Each scale's items were appropriately targeted to the subjects, and all three scales distinguished subjects into approximately three different levels. More than 90% of the raters used the three scales validly and had approximately the same degree of severity or leniency. The scales were valid across subjects with physical dysfunction and psychiatric conditions as well as subjects with no active diagnosed condition. Conclusion. The three scales of the OPHI-II are valid across age, diagnosis, culture, and language and effectively measure a wide range of persons. Raters can readily use the OPHI-II validly without formal training.