Validity of Person Matching in Vocational Interest Inventories

Research for more than 60 years has shown that entry into occupations can be predicted from scores on interest inventories at a rate better than chance (Donnay, 1997). The psychometric scoring methodologies used today by a majority of vocational interest inventories were developed in the 1920s and 1960s. Researchers are challenged with improving the theory and science behind vocational interest inventories to align them with current vocational constructions. In this study, validity comparisons were made between person matching and standard scoring based on 5,143 medical students who had taken a vocational interest inventory and had entered their medical residency. Person matching was found to improve differentiation between occupational groups and increase the amount of information offered in the scoring report; in addition, it could potentially increase occupational group assignment to advance vocational interest inventory validity.Keywords: person matching, career interest, narrative, assessment, hit rateVocational interest inventories help to clarify interests and promote oc- cupational exploration (Creed, Patton, & Prideaux, 2006; Ihle-Helledy, Zytowski, & Fouad, 2004). Interests are permanent enough (an in- traindividual correlation coefficient of .75 suggests high stability) and sufficiently unaffected by vocational training and experience to furnish a basis for predicting future behavior (Strong, 1943). Research for more than 60 years has shown that entry into occupations can be predicted from scores on interest inventories at a rate better than chance (Donnay, 1997). Follow-up studies ranging from 3 to 18 years suggest that hit rates for interest inventories can be between 32% and 69%, which is well above the chance expectancy rate (Donnay, 1997). Hit rates are operationally defined as an exact match between the individual's chosen occupation and the occupation suggested by the vocational interest inventory. The greater the accuracy with which a scoring method calculated a person's final occupational choice, the higher the hit rate reported.The present research investigated a rarely used psychometric scoring methodology known as person matching to potentially improve the validity of vocational interest inventories. There are two measures of the validity of a vocational interest inventory (Strong, 1943). First, validity rests on an interest inventory's ability to differentiate between specific occupational groups (Kuder, 1977a; Strong, 1943). Second, the interest inventory needs to assign individuals to membership in one or more occupational groups based on their interest inventory scores (Strong, 1943). Comparisons in validity between the standard scoring method of Strong (developed in 1927) and the person-match scoring method of Kuder (developed in 1977) were examined.Standard Scoring MethodStrong's (1943) scoring method is based in a modernist paradigm and compares individuals to occupational groups. Individuals are described as "patients" who take on a passive role by waiting for answers to be provided to them by assessments, others, or the environment so that they can make an occupational selection (Brott, 2004; Bujold, 2004). Predicting occupational choice results from objectively counting in- dividuals' responses to items on interest inventories, which can then be matched to the world of work (Bujold, 2004; Cohen, Duberley, & Mallon, 2004).Strong (1943) discovered empirically that occupational groups produced a pattern of responses on an interest inventory, which could then differ- entiate between the average member of that occupational group and the average individual in general (Crites, 1969). Strong's occupational scales eliminated similarities in interests and used only the differences in inter- est to set members of an occupation apart from general interest patterns (Campbell & Borgen, 1999; Case & Blackwell, 2008; Strong, 1943). He believed that creating occupational scales for each occupation was invaluable because interest in certain kinds of activities linked the test taker to real- world behavior in that occupation (Campbell & Borgen, 1999). …