According to the publisher, Psychological Assessment Resources, the Self-Directed Search (SDS) developed by Dr. John L. Holland is the mostly widely used career interest inventory in the world. It has been translated into over 25 different languages. The SDS is based on Dr. Holland’s RIASEC theory that both people and work and study environments can be classified according to six basic types: Realistic, Investigative, Artistic, Social, Enterprising, and Conventional (RIASEC). The SDS enables users to choose occupations and fields of study that best match their self-reported skills and interests. It is based on the idea that people whose job and work environments most closely match their personal style and interests tend to consider themselves satisfied and successful with the occupational choices they have made.
The SDS Form R (SDS:R) is the most common version of the instrument. In its assessment booklet, users answer questions about their occupational aspirations in a Daydreams section, which can be scored separately to yield a vocational aspirations code, or expressed interest code. Sections with lists of activities, competencies, and occupations follow the Daydreams section. The final section includes ratings for ability self-estimates across the six RIASEC areas. These latter five sections of the SDS:R can be self-scored to produce a three-letter summary code that designates the three personality types an individual most closely resembles. This is called the assessed code.
The SDS is both a stand-alone career planning simulation that imitates an interest inventory as well as a psychological test. The original paper-and-pencil SDS:R has been revised four times, most recently in 1994, and includes the Assessment booklet, the Occupations Finder (1,335 occupations employing 99 percent of U.S. workers and updated with additional information on technology occupations in 1999), and the You and Your Career booklet, which discusses the scientific ideas supporting the SDS, how to interpret the scores and codes, the personality characteristics associated with codes, and some suggestions for successful career planning. Normative data for the 1994 edition of SDS:R were derived from a nationally representative sample of 2,602 students (high school and college) and working adults in the United States.
While most counselors have basic information about the SDS:R paper version, the other varied SDS formats and versions are less widely known. A computer-based version of SDS:R provides for faster administration and more efficient use of the inventory. The computer generates a 10- to 12-page Interpretive Report for users based on SDS summary scores and a 1- to 3-page professional summary for counselors.
Besides these various formats of SDS:R, other versions of the SDS include Form E (Easy) for persons with poor English language or reading skills, SDS: Form CP (Career Planning) for adults working in organizations, and SDS: Career Explorer for middle school students. These alternative formats of the SDS have the same basic features of SDS:R.
In his writings, Holland has urged counselors to pay close attention to what persons say about the occupations they are considering. Occupational aspirations are equal to or exceed predictions of future occupational activity available in standardized inventories. In other words, persons’ expressed interests may be just as predictive of future occupational activity as their assessed interests.
An important innovation in the measurement of aspirations in the SDS Daydreams section was the coding of aspirations using the RIASEC typology. This procedure enables a counselor to examine not only the occupation named but also its RIASEC code. When the first two or three aspirations belong in the same RIASEC category, the predictive power of the first aspiration equals or exceeds the efficiency of an interest inventory.
The SDS has been described as a career planning simulation because it provides an opportunity to observe a career planning event under controlled conditions that might occur in real life. In this case, the SDS Assessment booklet provides a way for counselors to observe how persons may be engaging in educational and career decision making. The SDS is also a standardized assessment instrument. The items in the Assessment booklet have desirable psychometric properties and are based on RIASEC theory. The SDS has been subjected to the same rigorous test development standards as other professionally published tests, and the SDS manuals describe a complex, theory-based test development process begun in 1970.
The Activities section of the SDS:R Assessment booklet consists of 11 items for each of the six RIASEC types, and they cover hobbies and activities that are done for fun or leisure, and users can endorse them as “like” or “dislike.” These items are included in the SDS because they effectively measure interests in relation to RIASEC theory.
In the Competencies section, users describe their skills, the kinds of things they had learned to do in the past, as well as discuss the skills they might want to develop in the future. This kind of information is practically important, because it is reasonable to believe that persons completing a career assessment will consider their history of skills and education or work-related accomplishments. The Competencies section of the SDS:R includes 11 items that are marked “yes” or “no” for the six RIASEC areas.
The next section of the SDS:R is Occupations. Longer than the previous two sections, it includes 14 items (occupational titles) that are endorsed “yes” or “no” for each of the RIASEC areas. Holland included this section because he wanted to make sure he obtained a good measure of the person’s RIASEC typology and because he wanted to get a picture of the positive and negative feelings the person had for various occupational titles.
The final section of the SDS:R Assessment booklet is Self-estimates. It includes the six RIASEC scales, which are rated twice (from 1 to 7) with respect to ability and skill. Users are asked to rate themselves “as you really think you are when compared with other persons your own age.”
When the SDS was first introduced, some critics viewed it as “simplistic.” However, more recent reviews have noted that the use of Holland’s inventories is “extensive.” The SDS is unique in several ways: (a) It is self-administering, self-scoring, and self-interpreting; (b) it is based on Holland’s theory; and (c) it is supported by extensive research. The SDS is an inventory with desirable psychometric characteristics that incorporates a person’s history of vocational daydreams, which can be used to increase predictive validity and to form an impression of a person’s goals and background that encourages the immediate preliminary exploration of more than 1,000 occupations. Because it is self-scored and can be interpreted by most people, it encourages a person’s active participation in the resolution of career problems and questions.