The purpose of this study was to investigate the effectiveness of providing Holland's (1997) RIASEC interest inventory as a tool for Japanese high school students to narrow down their career choices and develop their vocational identity. It especially focused on how students reacted differently depending on their sex differences and job-seeking attitudes (occupational model or workplace/company model). Holland's theory assumes that an individual chooses his or her desired occupation ( occupational model), however, traditional Japanese job-seekers place more importance on choosing a desired workplace or a company (workplace/company model) and become generalists rather than choosing a single occupation. In such a culture, the effectiveness of Holland's career intervention needed to be carefully investigated before its application to the target culture.

A sample of 58 Japanese high school students temporarily residing in the U.S. participated in an experimental design on their development of vocational identity after receiving an intervention. Data were analyzed using a factorial Analysis of Covariance (ANCOVA). A McNemar chi-square significance of change was also used to analyze the impact of Holland's career intervention on students' attitudinal change in their job-seeking orientation. While these analyses did not reveal any statistically significant effects or differences, which may be due to the small sample and effect size, supplemental analyses revealed: (a) a statistically significant correlation between gain scores of vocational identity and a high level of Investigative interest; (b) a statistically significant interaction effect between the treatment condition and the levels of Investigative interest; (c) a statistically significant increase from the pretest to posttest vocational identity score with a small-medium effect size only for the treatment group; and (d) a statistically significant increase among members of the treatment group in the two items of the vocational identity questionnaire which asked about one's self-understanding.

Although the hypotheses tested in the present study did not find any statistically significant findings, the supplemental analyses supported the effectiveness of Holland's (1997) approach as a career counseling intervention. However, the effect sizes were somewhat small. This may be due to the experimental design which relied solely on written materials in order to eliminate extraneous variables and lacked a counselor's help in the instruction and interpretation of individuals' results. It is recommended in future research to integrate a counselor's help in an experimental design to add to the body of knowledge in this profession.