Stability of vocational interests among high school students

Adolescence, Fall, 1998 by Ronald L. Mullis, Ann K. Mullis, Deborah Gerwels

Holland (1973/1985) theorized that career choices are largely a function of personal factors (e.g., personality traits, self-knowledge, occupational knowledge) and environmental factors (e.g., family, school). In making career choices, individuals seek the type of environment that matches, or is congruent with, their personality type. Holland's construct of consistency, or stability, in the expression of vocational themes and basic interests was the primary focus of the present study.

The Strong-Campbell Interest Inventory (SCII; Hansen & Campbell, 1985) has long been used to identify career interests. Lunneborg (1977) provided evidence (concurrent and predictive validity) of the SCII's ability to ascertain present and future occupational membership. Naylor, Care, and Mount (1986) reported good concurrent validity between Holland's career typology and the SCII's occupational themes.

The stability of career interests continues to receive the attention of researchers and practitioners (Campbell, 1966; Hansen, 1984; Hansen & Stocco, 1980; Lunneborg, 1977; Prawat, Jones, & Hampton, 1979; Swanson & Hansen, 1988), particularly in regard to high school students, who have a variety of options. Hansen and Stocco (1980) found the SCII to be a useful measure of stability when testing adolescents and young adults at two time periods, three years apart. For their high school sample, coefficients ranged from -.21 to .92 for the Basic Interest scales and -.31 to .96 for Occupational Themes. The young adult sample yielded coefficients of -.28 to .96 for Basic Interests and .17 to .97 for Occupational Themes. Similarly, Swanson and Hansen (1988) found that college students were highly stable in their career interests over twelve years, and that these interests were significantly related to self-ratings of stability.

There remains a need to substantiate these earlier findings and to further validate Holland's theory and measurement of career interests. Aside from predicting future choices, understanding more about the career preferences of younger adolescents can assist educators and counselors in designing programs and instructional strategies that better meet the needs of this age group. For example, knowing developmental patterns of career preferences can help professionals expose male and female adolescents to a broader range of options. This continues to be an important issue because of inconsistent findings with regard to the stability of sex differences in vocational interests. Diamond (1975) has argued that because people increasingly see traditional sex roles as arbitrary, sex differences in career interests may be diminishing. In contrast, Hansen (1984) has concluded that, despite heightened consciousness, sex differences in vocational interests have remained stable.

In addition to the relevance of gender in emerging career preferences, Holland (1962) suggested that families, particularly their work patterns and social position, have a profound impact on their children's career interests. Holland reported that father's occupation was significantly related to son's career interests. Subsequent research has also found relationships between career interests and social class (Mortimer, 1976) and social influences (Bracher, 1982).

The magnitude and stability of individual and sociocultural influences on adolescents' career interests require further investigation. Thus, the present study examined the stability of career interests of high school students. In keeping with Holland's theory that both personal and environmental factors influence career interests over time, gender and socioeconomic status also were examined.

METHOD

Subjects

A subsample of 271 freshmen (48% males and 52% females) was drawn from a larger, cross-sectional study of 1,350 Midwestern high school students. They represented 71% of the original sample of freshmen (n = 382), and ranged in age from 14 to 15 years at the initial testing (follow-up testing occurred three years later). They were predominantly Caucasian and from two-parent families (88%), averaging 4.5 persons per family. They reported that their families had resided in their homes for an average of nine years. Parental occupations were categorized as professional, unskilled, and skilled, based on Hollingshead's Four-Factor Index of Social Position (Hollingshead, 1975). All mothers and fathers had completed high school and 48% had attended or completed college.

The mean scores of students who participated in the present, longitudinal research were compared with the scores of those who were not included. Using t tests, no significant differences were found between groups.

Measures

Students completed the Strong-Campbell Interest Inventory (Hansen & Campbell, 1985). The SCII includes RIASEC Occupational Themes, as well as 23 Basic Interest scales that are thought to reflect components of the former. RIASEC is an acronym for Holland's hexagonal system of six vocational-interest themes: Realistic (interest in working with things and gadgets, interest in working outdoors, need for structure); Investigative (interest in science such as mathematics and the physical sciences, work independently); Artistic (interest in creative expression such as writing and the arts, little need for structure); Social (interest in people, drawn toward the helping professions); Enterprising (prefer leadership roles aimed at achieving economic objectives); and Conventional (prefer well-structured environment and chain of command, tend to be a follower rather than a leader). The 23 Basic Interest scales (according to their most closely associated RIASEC theme) are: Agriculture, Nature, Adventure, Military, and Mechanical Activities (R); Science, Mathematics, Medical Science, and Medical Services (I); Music/Drama, Art, and Writing (A); Teaching, Social Services, Athletics, Domestic Arts, and Religion (S); Public Speaking, Law/Politics, Merchandising, Sales, and Business Management (E); and Office Practices (C). In addition to the SCII, demographic information (e.g., parents' occupation and education, family composition) was collected.