1. Strong Interest Inventory
Kristin Hodnefield

2. The Man Behind the Strong
The test was developed in 1927 by psychologist E.K. Strong, Jr. to help people exiting the military find jobs.
Strong developed several scales that contrasted groups of people, based on their answers.
This method of scaling, developed by Strong, has been very influential and has been used in several different questionnaires, including the Minnesota Multiphasic Personality Inventory (MMPI).
It was later revised by Jo-Ida Hansen, and David Campbell.
The Inventory has been revised 6 times over the years to reflect the continued development in the field.
The most recent edition (developed in 2004) is currently being published by CPP, Inc. based in California.

3. About the Strong Interest Inventory
The test was found to be at about the ninth-grade reading level.
It was designed for Students aged 13–14 and above.
However, the strong website does caution the person administering the test to keep in mind that “interests don’t' start to crystallize until between the ages of 16 and 18.”
The Strong is gender specific, so it matches your responses to the responses of your same gender.

4. What can the Strong be used for?
Career planning:
Support the development of employees by identifying jobs that best fit their interests.
Mid-career coaching:
Help employees choose between career paths by determining where their interests lie.
Supporting ‘plateaued’ employees:
Cater to those who feel they have reached the limit of movement in an organization by identifying alternative activities, projects or entire career paths that better fit their interests.
Career change:
Help people understand their job satisfaction and explore the reasoning for that, and obstacles to a potential career change.

5. What can the Strong be used for?
Outplacement:
Use the Strong to help individuals identify a fulfilling career path and prepare for a career plan that utilizes their transferable skills.
Career Counseling:
Identify your clients’ interests, and provide them with a framework for organizing their interests into general as well as specific categories within the professional world.
Help them identify potentially relevant occupations that may not have been previously considered.
Retirement:
Help employees nearing retirement explore their interests and plan a fulfilling and meaningful life after work.

6. The Newest Edition of the Strong
The newly revised inventory (2004) consists of 291 items that measure an individual's interest in six areas:
Area
Number of Questions in Each Area
Occupations
107
Subject Areas 46
Activities 85
Leisure Activities 28
People 16
Your Characteristics 9

7. Test Layout
The first 282 items are answered by choosing one of the following options:
“strongly like”
“like”
“indifferent”
“dislike”
“strongly dislike”
The remaining 9 items in the "Your Characteristics" section are answered the same way but with different options:
"strongly like me”
"like me”
"don’t know”
"unlike me”
"strongly unlike me”

8. Sections of the Strong Section 1: Section 2: Section 3: Section 4:
General Occupation Themes
Section 2:
Basic Interest Skills
Section 3:
Occupational Scales
Section 4:
Personal Style Scales
Section 5:
Profile Summary
Section 6:
Response Summary

9. Section 1: General Occupational Themes
The General Occupational Themes section describes your interests, work activities, potential skills and your personal values in six areas:
Realistic (R)
Investigative (I)
Artistic (A)
Social (S)
Enterprising (E)
Conventional (C)
You receive a 3 letter code describing your highest themes.
Ex: SEC (Social, Enterprising, Conventional)
The GOTs are global concepts. Numerous resources (eg. websites and books) make use of the themes, this makes them useful inside or outside the Strong framework.

10. General Occupational Theme

11. General Occupational Theme

12. Section 2: Basic Interest Scales
The Basic Interest Scales identify specific interest areas within the six General Occupational Themes.
Indicating areas likely to be most motivating and rewarding for the individual.
The Basic Interest Scales are ideal for:
Assisting clients in understanding the underlying interests measured by the GOT
Highlighting a client’s ‘likes’ and ‘dislikes’ within each GOT
Shedding light on major themes in the individual’s interests, when used in conjunction with the Occupational Scales
Providing a comprehensive representation of the client’s interests.

13. Basic Interest Scales

14. Basic Interest Scales

15. Section 3: Occupational Scales
The Occupational Scales compares your likes and dislikes with people who are satisfied working in various occupations.
Indicating your likely compatibility of interests.
The Strong highlights the top 10 occupations most closely aligned with your interests.
The occupations are just some of the many occupations linked to your interests.
It is not indicative of the career your should absolutely pursue.
Your score on the Occupational Scale shows how similar your interests are to those of people of your gender who have been working, and are satisfied with that occupation.
The higher your score, the more likes and dislikes you share with those individuals satisfied with their employment.

16. Occupational Scales

17. Occupational Scales

18. Occupational Scales

19. Occupational Scales

20. Occupational Scales

21. Occupational Scales

22. Occupational Scales

23. Section 4: Personal Style Scales
Personal Style Scales describe preferences related to work style, learning style, leadership style, risk taking and teamwork.
This provides insight into work and education environments most likely to fit best.
Personal Style Scales help to:
Refine their choices based on information about their personal style.
Identify the style they will feel most comfortable using when working in their chosen career.
Increase job satisfaction.
Determine how alternatives for further learning or training may fit with their learning style.
Identify their interest in assuming a particular leadership style.
Identify how much risk they are willing to take in choosing or changing careers.

24. Personal Style Scales

25. Personal Style Scales

26. Section 5: Profile Summary
Profile Summary provides a graphic representation of your overall profile for easy reference

27. Profile Summary

28. Section 6: Response Summary
Response summary summarizes your responses within each category of the Strong.
This provides data to be useful with a career professional.
The Response Summary is a useful overview of an individual’s results, providing the counselor with information on:
The consistency with which the client completed the inventory. The range of possible scores for the typicality index is 0–24; scores of 17 or higher are considered to be reflective of consistent responding.

29. Response Summary

30. What the Strong Measures
The Strong assessment measures interests in four main categories of scales: General Occupational Themes (GOTs), Basic Interest Scales (BISs), Personal Style Scales (PSSs), and Occupational Scales (OSs).
6 GOTs measure basic categories of occupational interests—Realistic, Investigative, Artistic, Social, Enterprising, and Conventional (RIASEC)—based on John Holland’s theory (Holland, 1959).
30 BISs measure clusters of interest related to the GOTs in areas such as Athletics, Science, Performing Arts, and Sales.
5 PSSs—Work Style, Learning Environment, Leadership Style, Risk Taking, and Team Orientation—measure preferences for and comfort levels with styles of living and working. Personal Style Scales were added to the inventory in 1994.
260 Oss (130 for men, 130 for women) measure the extent to which a person’s interests are similar to the interests of people of the same gender working in 130 diverse occupations, such as Accountant, Bartender, and Computer Programmer.

31. Administration of the Strong
The strong is able to be administered online.
Results from the online assessment are available within days of taking the Strong.
The strong is also available by scantron paper copy.
The paper copies are processed by CPP in California and can take up to two-four weeks for results.
Access to administration of the Strong questionnaire is restricted to those holding the BPS Test User: Occupational, Ability qualification.

32. Scoring of the Strong
The newly revised version of this test can typically be taken in minutes after which the results must be scored by computer. After scoring, an individual can then view how their personal interests compare with the interests of people in a specific career field.
Access to the comparison database and interpretation of the results usually ranges from $30-$45 for a full report.
The results include:
Scores on the level of interest on each of the six General Occupational Themes.
Scores on 30 Basic Interest Scales (e.g. art, science, and public speaking)
Scores on 244 Occupational Scales which indicate the similarity between the respondent's interests and those of people working in each of the 122 occupations.
Scores on 5 Personal Style Scales (learning, working, leadership, risk-taking and team orientation).
Scores on 3 Administrative Scales used to identify test errors or unusual profiles.

33. Norms
The current norm sample for the Strong is called the General Representative Sample (GRS) and consists of 2,250 individuals (50% men, 50% women). The GRS is generally representative of the racial and ethnic makeup of the U.S. workforce (Donnay, Morris, Schaubhut, & Thompson, 2005).
This wide range of norming groups indicates a strong test sampling.
Although, specific cultural, racial and ethnic makeups of the GRS are not available, potentially indicating a less than adequate representation.

34. Reliability
All six revised General Occupational Themes (GOTs) possessed internal consistency reliability of at least 0.91.
Internal consistency reliabilities of all scales are high.
General Occupational Themes (GOT) reliabilities range from .90 to .95.
Basic Interest Scales (BISs) from .80 to .92.
Personal Style Scales (PSSs) from .82 to .87.
Occupational Scales (OSs) were not tested for reliability because the scales contain items with heterogeneous content and are empirically derived.
These high reliability scales indicate the overall effectiveness of the assessment.

35. Validity
Studies have found the General Occupational Themes (GOTs) to be predictive of work-related variables (Donnay & Borgen, 1996; Rottinghaus, Lindley, Green & Borgen, 2002).
Research has shown the Basic Interest Scales (BISs) can accurately distinguish occupations (Borgen & Lindley, 2003; Isaacs, Borgen, Donnay & Hansen, 1997; Larson & Borgen, 2002).
Initial validity studies of the 30 BIS show that as a group they explain 68–78% of the variance in broad occupational groups, and 92–93% of the variance in college major groups.
Validity of the Personal Style Scales (PSSs) has been supported through research showing their relationships with the Skills Confidence Inventory (Tuel & Betz, 1998) and MBTI instruments (Hammer & Kummerow, 1996).
Validity of the Occupational Scales (OSs) has been demonstrated in research showing their ability to predict the occupations that people will eventually enter (Strong, 1935, 1955; Campbell, 1966; Harmon, 1969; Hansen & Swanson, 1983; Dirk & Hansen, 2004).

36. Adequacy of the Strong
When compared to other methods and techniques of observation, the Strong is significantly easier to administer and interpret. The practitioner does not need to be an experienced career counselor to interpret the results.
The Strong is the perfect companion to psychometric assessments such as the MBTI® and 16PF® instruments. Our personality, which has a lot to say about our preferred working environments, along with our interests, as assessed by the Strong, can help us make better career decisions to fit our needs.

37. Issues with the Strong
Despite its versatility, the Strong is not designed to prescribe career paths. It is a simply a tool for discussion and exploration.
It is important that clients are aware the career paths outlined are not a ‘set in stone’ list of careers they will succeed in.
The Strong does not assess knowledge, skills or abilities in a given field.

38. Benefits of the Strong Helps you to:
Identify career options consistent with your interests.
Choose appropriate education and training relevant to your interests.
Understand aspects of your personality associated with your interests.
Determine preferred learning environments.

39. Purchasing the Strong
Access to the Strong questionnaire and associated products (including the Manual) is restricted to those holding the BPS Test User: Occupational, Ability qualification (formerly Level A)
You are able to take the test online and get your own results, however in order to have access to purchasing and administering the test to others, you need to have the qualifications listed above.
You are able to be certifited online by taking a course offered by the OPP.
User Guide and Manuals typically run from $

40. Website References https://www.cpp.com/products/strong/index.aspx
interest-inventory.htm
ucts/Strong_Interest_Inventory_Brief_Guide.pdf

41. Article References
Borgen, F. H., & Lindley, L. D. (2003). Optimal functioning in interests, self-efficacy, and personality. In W. B. Walsh (Ed.), Counseling psychology and optimal human functioning (pp ). Hillsdale, NJ: Lawrence Erlbaum Press. 

Campbell, D. P. (1966). Occupations 10 years later of high school seniors with high scores on the SVIB life insurance salesman scale. Journal of Applied Psychology, 50, 

Dirk, B. J., & Hansen, J. C. (2004, February). Development and validation of discriminant functions for the Strong Interest Inventory®. Journal of Vocational Behavior, 64 (1), 

Donnay, D. A. C., & Borgen, F. H. (1996). Validity, structure, and content of the 1994 Strong Interest Inventory®. Journal of Counseling Psychology, 43, 

Hammer, A. L., & Kummerow, J. K. (1996). Strong and MBTI® career development guide (rev. ed.). Mountain View, CA: CPP, Inc. 

Hansen, J. C., & Swanson, J. L. (1983). Stability of interests and the predictive and concurrent validity of the 1981 Strong-Campbell Interest Inventory for college majors. Journal of Counseling Psychology, 30, 

Harmon, L. W. (1969). The predictive power over 10 years of measured social service and scientific interests among college women. Journal of Applied Psychology, 53, 

Holland, J. L. (1959). A theory of vocational choice. Journal of Counseling Psychology, 6, 

Isaacs, J. Borgen, F. H., Donnay, D. A. C, & Hansen, T. A. (1997). Self-efficacy and interests: Relationships of Holland themes to college major. Poster presented at the annual meeting of the American Psychological Association, Chicago, IL. 

Larson, L. M. & Borgen, F. H. (2002). Convergence of vocational interests and personality: Examples in an adolescent gifted sample. Journal of Vocational Behavior, 60, 

Rottinghaus, P. J., Lindley, L. D., Green, M. A., & Borgen, F. H. (2002). Educational aspirations: The contribution of personality, self-efficacy, and interests. Journal of Vocational Behavior, 61, 

Strong, E. K., Jr. (1935). Predictive value of the Vocational Interest Test. Journal of Educational Psychology, 26, 332. 

Strong, E. K., Jr. (1955). Vocational interests 18 years after college. Minneapolis: University of Minnesota Press. 

Tuel, B. D., & Betz, N. E. (1998). Relationships of career self-efficacy expectations to the Myers-Briggs Type Indicator® and the Personal Style Scales. Measurement and Evaluation in Counseling and Development, 31,