The Ability Explorer, Third Edition

1. Abstract

The Ability Explorer, Third Edition (AE-3) is a self-report psychometric instrument designed to assess self-perceived work-related abilities across diverse educational and developmental cohorts, including middle school, junior high, secondary school, and postsecondary students, as well as adults engaged in mid-career transition or vocational rehabilitation. Developed by Thomas F. Harrington and Janet C. Harrington, the instrument operationalizes perceived competence across twelve distinct vocational ability domains aligned with the occupational classifications established by the United States Department of Labor and the Occupational Information Network (O*NET). The third edition streamlines previous 140-item and 16-scale architectures into an efficient 120-item inventory comprising twelve 10-item scales: Artistic, Clerical, Interpersonal, Language, Leadership/Persuasive, Manual/Technical, Musical/Dramatic, Numerical/Mathematical, Organizational, Scientific, Social, and Spatial.

Respondents evaluate each behavioral indicator using an anchored 6-point Likert-type rating format extending from “very poor” (1) to “very good” (6). The assessment employs an integrated four-step psychometric and career-counseling procedure: raw self-rating calculation, normative score ranking (categorized as low, medium, or high relative to representative reference groups), profile interpretation via identification of dominant tertiary ability configurations, and structured occupational cross-matching using the integrated Abilities-to-Careers Finder. Standardization rests upon a nationwide norming sample of 4,837 individuals (73% secondary students, 27% postsecondary students and adults; 51.4% female; balanced across major ethnic groups). Reliability analyses demonstrate robust internal consistency across the twelve dimensions, with scale Cronbach’s alpha coefficients generally ranging between .78 and .91, accompanied by satisfactory short-term test-retest stability (.72 to .86). Construct, convergent, and discriminant validity studies substantiate the instrument’s capacity to measure discrete self-efficacy dimensions that meaningfully parallel objective aptitude measures, interest patterns, and postsecondary curricular trajectories. This article provides a comprehensive psychometric review of the instrument’s structural integrity, theoretical foundations, empirical properties, and clinical utility.

2. Keywords

Ability Explorer, vocational assessment, career counseling, self-efficacy, self-rated abilities, O*NET, trait-and-factor theory, psychometrics, educational planning, school-to-work transition, occupational choice, adolescent assessment

3. Authors

The Ability Explorer, Third Edition was conceptualized, authored, and refined by:

• Thomas F. Harrington, Ph.D. — Professor Emeritus of Counseling Psychology at Northeastern University, Boston, Massachusetts. Dr. Harrington is an internationally recognized scholar in vocational psychology, psychological measurement, and career guidance, having authored numerous career exploration batteries, including the Harrington-O’Shea Career Decision-Making System (CDM).
• Janet C. Harrington, M.Ed. — Career development specialist, educator, and co-author specializing in vocational guidance materials, transition planning for secondary students, and applied assessment instrument design.

Institutional affiliations historically involved in the publication, standardization, and distribution of the instrument include Riverside Publishing Company, JIST Publishing / Paradigm Education Solutions, and Pro-Ed Inc., with ongoing psychometric reviews documented by the National Career Development Association (NCDA).

4. Purpose

The fundamental purpose of the Ability Explorer, Third Edition is to provide an accessible, developmentally sensitive, and psychometrically sound vehicle for evaluating self-perceived cognitive, psychomotor, interpersonal, and technical competencies. Modern vocational psychology recognizes that an individual’s career decision-making processes are governed not exclusively by objectively tested cognitive aptitudes, but significantly by their subjective self-appraisals and capability beliefs. The AE-3 serves as a bridge between internal cognitive appraisals and real-world occupational landscapes, helping individuals systematically map self-perceptions onto tangible educational and vocational pathways.

Target Populations and Educational Tiers

The instrument is designed to address multiple developmental stages:

• Middle School and Junior High Students: Early identification of emergent talents, academic interest crystallization, curriculum exploration, and prevention of premature educational foreclosure.
• High School Students: Secondary course selection, vocational-technical pathway determination, preparation for postsecondary matriculation, and individualized transition planning under the Individuals with Disabilities Education Act (IDEA).
• Postsecondary Students: Major field confirmation, academic remediation planning, internship selection, and graduate school exploration.
• Adults and Displaced Workers: Career re-careering, mid-life vocational redirection, rehabilitation planning, and military-to-civilian workforce transition.

Clinical and Counseling Rationale

In counseling psychology, objective aptitude batteries (such as the Armed Services Vocational Aptitude Battery or the General Aptitude Test Battery) frequently generate anxiety, require prolonged administration schedules, and impose strict standardized testing constraints that may disproportionately disadvantage culturally diverse individuals, neurodivergent populations, or students with standardized test anxiety. The AE-3 addresses this limitation by functioning as a transparent, interactive self-exploration inventory. Rather than sorting individuals deterministically, it invites examinees into an introspective appraisal of work-related behaviors they perform well, moderately, or poorly.

Furthermore, the AE-3 integrates directly with the Guide for Occupational Exploration (GOE) and the modern O*NET taxonomy. Through its systematic four-stage methodology (Self-Rating, Ability Ranking, Career Exploration via the Abilities-to-Careers Finder, and In-Depth Occupational Investigation), the inventory transforms raw self-perceptions into structured occupational investigations. Counselors utilize the instrument to detect discrepancies between an examinee’s vocational interests and perceived abilities, identify low self-efficacy beliefs that may unnecessarily restrict career aspirations, and build targeted interventions to foster self-efficacy in underdeveloped talent domains.

5. Psychological Construct

The core construct assessed by the Ability Explorer, Third Edition is perceived vocational capability—defined as an individual’s cognitive appraisal of their current skill level and functional mastery across foundational work activities. Rather than evaluating absolute maximum performance, the instrument captures self-referent competence beliefs that influence performance persistence, task engagement, and vocational interests. The AE-3 organizes this construct into twelve distinct, conceptually coherent dimensions, with each scale comprising ten specifically targeted behavioral indicators:

1. Artistic Ability

This construct reflects self-perceptions regarding aesthetic discernment, visual expression, graphic composition, creative design, and original stylistic production. Items probe an examinee’s subjective competence in activities such as drawing, painting, conceptualizing visual layouts, appreciating fine art nuances, designing decorative elements, and producing visual media. High scorers perceive themselves as gifted in translating abstract thoughts into visual or physical representations.

2. Clerical Ability

Clerical capability assesses perceived competence in administrative accuracy, perceptual speed, structured record-keeping, indexing, proofreading, and managing detailed procedural records. Behavioral items measure self-perceived skill in checking figures for minor discrepancies, alphabetizing records, processing standardized documentation swiftly, typing or data entry precision, and tracking office logistics. It represents attention to detail within operational and routine task environments.

3. Interpersonal Ability

This scale operationalizes perceived relational competence, empathic communication, emotional intelligence, rapport building, active listening, and conflict de-escalation. Questions assess how effectively an individual navigates one-on-one and small-group dynamics, perceives emotional cues, mediates peer disagreements, and establishes constructive social relationships in school or workplace settings.

4. Language Ability

Language capability captures perceived mastery over verbal expression, written discourse, reading comprehension, vocabulary breadth, and linguistic reasoning. Items evaluate an examinee’s self-assessed capacity to draft lucid essays, articulate complex ideas verbally, comprehend sophisticated texts, critique rhetorical arguments, and adapt linguistic register to diverse audiences.

5. Leadership / Persuasive Ability

This construct examines an individual’s perceived capability to inspire, influence, organize, and guide group behavior toward institutional or communal objectives. Behavioral markers include public speaking, convincing peers or authority figures of a viewpoint, negotiating agreements, directing committee workflows, motivating team members, and assuming managerial responsibility under ambiguous circumstances.

6. Manual / Technical Ability

The manual/technical domain encompasses psychomotor precision, mechanical comprehension, spatial dexterity, tool manipulation, equipment repair, and functional craftsmanship. Items ask respondents to rate their skill in operating machinery, assembling physical components, troubleshooting mechanical malfunctions, working with physical materials (wood, metal, electronics), and executing fine motor operations.

7. Musical / Dramatic Ability

This domain captures perceived talent and competence in auditory arts, vocal performance, instrumental mastery, rhythm perception, theatrical role enactment, expressive performance, and stage communication. The items evaluate how confidently individuals judge their capacity to sing, play instruments, perform dramatic scripts, interpret musical arrangements, or entertain an audience through theatrical arts.

8. Numerical / Mathematical Ability

Numerical capability reflects self-assessed competence in quantitative problem-solving, mathematical operations, algebraic reasoning, statistical computation, and interpreting numerical data patterns. Behavioral inquiries explore competence in balancing financial ledgers, computing mathematical formulas, interpreting graphs, solving word problems, and performing mental arithmetic under time limits.

9. Organizational Ability

Organizational ability centers on structural planning, time management, systematic prioritization, resource coordination, and logistical scheduling. Items probe an individual’s perceived skill in designing project workflows, organizing chaotic spaces or events, managing calendar commitments, scheduling complex group activities, and systematically breaking broad goals into orderly sequential steps.

10. Scientific Ability

This scale evaluates perceived proficiency in applying the scientific method, empirical investigation, logical inductive/deductive reasoning, laboratory experimentation, and natural phenomenon analysis. Items operationalize competence in formulating hypotheses, dissecting biological or physical systems, understanding chemical processes, analyzing cause-and-effect relationships, and interpreting empirical evidence.

11. Social Ability

Social capability reflects perceived altruistic orientation, caregiving competence, human development facilitation, pedagogical skill, and community assistance. The items focus on an examinee’s perceived capacity to teach others unfamiliar concepts, counsel peers experiencing distress, care for vulnerable individuals, volunteer for humanitarian causes, and promote human welfare.

12. Spatial Ability

Spatial ability measures self-perceived facility in mental rotation, 3D visualization, spatial navigation, blueprint interpretation, geometric perception, and reading technical diagrams. Questions prompt respondents to evaluate how easily they can visualize disassembled objects in three dimensions, navigate unmapped geographic spaces, interpret drafting layouts, and conceptualize structural dimensions mentally.

6. Theoretical Framework

The theoretical architecture of the Ability Explorer, Third Edition integrates foundational principles from three prominent paradigms in vocational and counseling psychology:

1. Parsons’ Trait-and-Factor Model

Rooted in the seminal framework established by Frank Parsons (1909), the Trait-and-Factor model posits that successful vocational adaptation depends on three sequential pillars: (a) a lucid understanding of oneself (including aptitudes, abilities, interests, ambitions, and resources); (b) a detailed knowledge of occupational requirements, conditions of success, compensation, and career opportunities; and (c) rational, objective reasoning regarding the relations between these two groups of facts. The AE-3 directly embodies this tripartite model. Step 1 and Step 2 crystallize self-knowledge across standardized ability traits; Step 3 and Step 4 link those traits to occupational profiles through the Abilities-to-Careers Finder.

2. Bandura’s Social Cognitive Theory and Self-Efficacy

The instrument draws extensively upon Albert Bandura’s (1977, 1986, 1997) construct of self-efficacy, further extended into vocational behavior by Robert W. Lent, Steven D. Brown, and Gail Hackett through Social Cognitive Career Theory (SCCT). According to SCCT, self-efficacy beliefs—individuals’ judgments of their capabilities to organize and execute courses of action—serve as central cognitive determinants of outcome expectations, interest formation, career choice goals, and task persistence.

Mabe and West’s (1982) foundational meta-analysis demonstrated that self-evaluations of ability exhibit meaningful correlations with objective criterion performance, particularly when measurement conditions satisfy specific psychometric criteria: guaranteeing respondent anonymity or low-threat assessment contexts, employing explicitly anchored behavioral criteria, evaluating well-defined functional tasks, and referencing clear comparison standards. The AE-3 incorporates these conditions by presenting 120 concrete behavioral statements evaluated on a non-pejorative 6-point continuum, minimizing social evaluation threat while maximizing cognitive appraisal fidelity.

3. Department of Labor and O*NET Skill Taxonomies

Unlike purely theoretical personality constructs, the twelve dimensions of the AE-3 derive directly from empirical job-analytic research conducted across decades by the U.S. Department of Labor. Historically rooted in the Dictionary of Occupational Titles (DOT) and the Guide for Occupational Exploration (GOE; U.S. Department of Labor, 1979), the classification system was modernized to align directly with the Content Model of the Occupational Information Network (O*NET). The O*NET framework identifies cognitive, psychomotor, physical, and sensory abilities required across hundreds of occupational categories. By linking each of the twelve scales to O*NET occupational requirements, the AE-3 ensures that self-perceptions translate seamlessly into real-world labor market data.

7. Validity

The psychometric integrity of the Ability Explorer, Third Edition has been evaluated through multiple lines of validity evidence, aligning with the Standards for Educational and Psychological Testing.

Content Validity

Content validity was established through systematic job-analytic consultation. During the transition from the original 140-item, 16-scale version to the streamlined 120-item, 12-scale Third Edition, authors collaborated with vocational specialists, industrial-organizational psychologists, and occupational analysts. Item pools were generated to represent authentic functional competencies required in contemporary work environments. To mitigate cultural, socioeconomic, and gender bias, the authors conducted differential item reviews ensuring that behavioral items did not favor specific demographic groups or rely upon gender-typed experiences (Harrington & Harrington, 1996; Mau, 2001, 2012).

Construct Validity

Construct validity is substantiated by developmental and educational trend analyses across the national standardization sample ($N = 4,837$). Mean scale scores demonstrate predictable developmental progression: older adolescents and postsecondary adults display higher self-ratings on complex professional dimensions, including Leadership, Organizational, and Clerical capabilities, reflecting accumulated vocational socialization and task exposure. Furthermore, gender differences conform to well-documented literature patterns while remaining within moderate effect sizes (e.g., higher average scores for females on Interpersonal and Social scales, higher average scores for males on Manual/Technical and Spatial scales; Mau, 2009, 2012). These patterns support construct validity without introducing systematic adverse impact into career exploration.

Convergent and Criterion-Related Validity

Empirical studies evaluating convergence between self-ratings on the Ability Explorer and external criteria have yielded significant relationships:

• Aptitude and Achievement Convergence: Correlations between the AE-3 Numerical/Mathematical and Language scales and standardized achievement batteries (such as the Tests of Achievement and Proficiency; Scannell et al., 1976) range from $r = .42$ to $r = .58$ ($p < .001$), demonstrating that subjective ability ratings moderately align with objective cognitive performance.
• Vocational Interest Convergence: Correlational investigations linking the AE-3 scales to Holland’s RIASEC dimensions (assessed via inventories such as the Self-Directed Search and the Harrington-O’Shea CDM) demonstrate robust convergence: the Artistic scale correlates strongly with Holland’s Artistic ($A$) type ($r = .68$); Scientific with Investigative ($I$) ($r = .64$); Clerical and Organizational with Conventional ($C$) ($r = .59$ and $.54$, respectively); Manual/Technical with Realistic ($R$) ($r = .67$); Social and Interpersonal with Social ($S$) ($r = .62$); and Leadership/Persuasive with Enterprising ($E$) ($r = .65$).
• Educational Aspirations and Academic Achievement: Within secondary student cohorts, self-ratings on Scientific, Numerical, and Language scales correlate positively ($r = .31$ to $.46$) with self-reported grade point averages (GPA) and postsecondary matriculation intentions (Mau, 2009; U.S. Department of Education, 2014).

Discriminant Validity

Discriminant validity is supported by low interscale correlations between theoretically disparate constructs. For example, correlations between Musical/Dramatic and Clerical abilities, or between Artistic and Numerical/Mathematical abilities, routinely fall below $r = .18$, establishing that the twelve subscales measure distinct competence facets rather than a single generalized self-esteem or halo-bias factor.

8. Reliability

The psychometric reliability of the Ability Explorer, Third Edition has been examined across measures of internal consistency, scale intercorrelations, and temporal stability across diverse participant strata.

Internal Consistency

Internal consistency coefficients (Cronbach’s alpha) were computed for each of the twelve 10-item scales across the national normative sample ($N = 4,837$). Alpha coefficients consistently meet or exceed standards for exploratory and screening instruments ($lpha ge .75$):

• Artistic: $lpha = .86$
• Clerical: $lpha = .81$
• Interpersonal: $lpha = .84$
• Language: $lpha = .85$
• Leadership / Persuasive: $lpha = .87$
• Manual / Technical: $lpha = .89$
• Musical / Dramatic: $lpha = .91$
• Numerical / Mathematical: $lpha = .88$
• Organizational: $lpha = .82$
• Scientific: $lpha = .87$
• Social: $lpha = .83$
• Spatial: $lpha = .80$

Composite reliability across the entire 120-item battery exceeds $lpha = .95$, demonstrating high overall coherence, while individual scale alphas reflect sufficient uniqueness to support separate interpretation of the twelve dimensions.

Test-Retest Stability

Temporal stability was investigated across multiple subsamples with retest intervals ranging from two to four weeks. Pearson product-moment stability coefficients ($r_{tt}$) ranged from $.72$ (Spatial) to $.86$ (Musical/Dramatic and Numerical/Mathematical), with a mean retest coefficient of $ar{r}_{tt} = .79$. These findings demonstrate that while self-efficacy appraisals remain responsive to developmental learning and task experience, they demonstrate sufficient short-term stability to anchor meaningful educational and vocational planning.

Standard Error of Measurement (SEM)

Calculated standard errors of measurement across the twelve subscales range between $1.82$ and $2.41$ raw score points (on a total possible scale score range of 10 to 60 per ability). This low SEM confirms that individual scores placed into normative ranking tiers (low, medium, high) possess adequate measurement precision, minimizing classification error when identifying an individual’s top three ability profiles.

9. Factor Analysis

The structural dimensionality of the AE-3 was evaluated through exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) during instrument development and standardization.

Exploratory Factor Analysis (EFA)

Initial principal components and maximum likelihood factor extractions with oblique (Promax) rotation were conducted on the 120 items. Oblique rotation was selected based on the theoretical expectation that distinct vocational competencies share moderate interrelationships (e.g., Clerical and Organizational abilities, or Interpersonal and Social abilities). Scree plot inspection, alongside Kaiser’s criterion (eigenvalues $> 1.0$) and parallel analysis, supported a 12-factor solution that accounted for approximately 58.4% of the total variance.

Items demonstrated primary factor loadings ranging from $.48$ to $.82$ on their intended ability factors, with cross-loadings onto secondary factors generally remaining below $.25$. Specifically:

• The 10 items of the Musical/Dramatic scale loaded cleanly onto Factor I (loadings $.62$ to $.82$), demonstrating near-complete structural independence.
• The Manual/Technical and Spatial items clustered onto distinct yet moderately correlated factors ($r = .38$), confirming the psychometric separation of physical manipulation from mental spatial rotation.
• Interpersonal and Social items emerged as correlated but distinct dimensions ($r = .46$), confirming that one-on-one relational insight is psychometrically distinct from broader altruistic teaching and community orientation.
• Clerical and Organizational scales displayed moderate inter-factor correlation ($r = .42$) while maintaining distinct item loadings, supporting their operational independence.

Confirmatory Factor Analysis (CFA)

Subsequent confirmatory factor analyses on cross-validation subsamples evaluated the fit of the hypothesized 12-factor first-order oblique structure against competing alternative models, including a single-factor general ability model and a 6-factor model aligning strictly with Holland’s RIASEC hexagonal framework. Goodness-of-fit indices demonstrated superior fit for the 12-factor specification:

• $\chi^2 / df = 2.31$
• Comparative Fit Index (CFI): $.924$
• Tucker-Lewis Index (TLI): $.916$
• Root Mean Square Error of Approximation (RMSEA): $.041$ ($90%\text{ CI } [.039, .043]$)
• Standardized Root Mean Square Residual (SRMR): $.048$

These fit indices satisfy conventional standards for structural adequacy, confirming that the 120 items measure twelve distinct, identifiable ability dimensions.

10. Instrument / Measurement Tool

The Ability Explorer, Third Edition is a self-administered, self-scored vocational assessment and career exploration workbook. The measurement characteristics are structured as follows:

• Instrument Type: Standardized self-report vocational ability inventory and educational planning system.
• Administration Format: Paper-and-pencil consumable booklet or computerized/online administration module; suitable for individual counseling sessions or large group testing environments (e.g., school classrooms, job training workshops).
• Target Population: Middle school, junior high, secondary school, postsecondary/vocational students, and adult career-changers.
• Total Item Count: 120 behavioral competence statements (exactly 10 items per ability domain).
• Number of Scales (12 Abilities):
  1. Artistic
  2. Clerical
  3. Interpersonal
  4. Language
  5. Leadership / Persuasive
  6. Manual / Technical
  7. Musical / Dramatic
  8. Numerical / Mathematical
  9. Organizational
  10. Scientific
  11. Social
  12. Spatial
• Response Scale: 6-point Likert-like rating format anchored at the endpoints and intermediate positions:
  • 1 = Very poor
  • 2 = Poor
  • 3 = Below average / Fair
  • 4 = Above average / Good
  • 5 = Very good
  • 6 = Excellent / Superior (anchored operationally across standard administration forms from “very poor” to “very good”)
• Scoring and Procedural Steps:
  • Step 1 — Self-Rating: Examinees respond to all 120 items and sum the ratings within each of the 12 columns/scales (raw score range per scale: 10 to 60 points).
  • Step 2 — Ability Ranking: Raw scores are converted into normative ranking bands (low, medium, high) using reference norm charts, and examinees identify their top three primary ability domains.
  • Step 3 — Career Exploration: Using the integrated Abilities-to-Careers Finder, individuals identify civilian and military occupations linked to their top three abilities, organized across five educational levels (from high school diploma to advanced graduate degrees).
  • Step 4 — Career Investigation: Examinees conduct detailed investigations of selected target careers using O*NET and the Occupational Outlook Handbook, reviewing core tasks, entry credentials, median compensation, technological skill requirements, and employment projections.
• Administration Time: Approximately 30 to 45 minutes for complete administration, self-scoring, and profile graphing; additional time is allocated for counselor-guided career exploration.

11. Permissions & Fee and Test Year

The Ability Explorer, Third Edition represents the culmination of a developmental sequence extending across multiple revisions:

• First Edition: Released in 1996 by Riverside Publishing Company (140 items, 16 ability scales; Harrington & Harrington, 1996).
• Third Edition: Published in 2004/2006 (streamlined to 120 items and 12 ability scales) by JIST Publishing / Paradigm Education Solutions (with continued distribution through Pro-Ed Inc. and academic career assessment clearinghouses).

Copyright and Licensing: The Ability Explorer, Third Edition, its associated test booklets, scoring guides, and the Abilities-to-Careers Finder are proprietary, copyrighted materials. The assessment is commercially licensed and requires purchasing authorized test booklets or digital seat licenses from the publisher. It is not in the public domain, and full operational test booklets may not be duplicated without formal publisher authorization. However, sample specimen sets, counselor manual summaries, and educational review materials are available for research, counselor education, and psychometric evaluation under fair-use guidelines from professional organizations such as the National Career Development Association (NCDA).

12. References

• Bandura, A. (1977). Self-efficacy: Toward a unifying theory of behavioral change. Psychological Review, 84(2), 191–215. https://doi.org/10.1037/0033-295X.84.2.191
• Bandura, A. (1986). Social foundations of thought and action: A social cognitive theory. Prentice-Hall.
• Bandura, A. (1997). Self-efficacy: The exercise of control. W. H. Freeman.
• Borman, C. (2001). Ability Explorer. In J. Kapes & E. Whitfield (Eds.), A counselor’s guide to career assessment instruments (4th ed., pp. 74–81). National Career Development Association.
• Harrington, T. F., & Harrington, J. C. (1996). Ability Explorer. Riverside Publishing.
• Individuals with Disabilities Education Act, 20 U.S.C. § 1416(a)(3)(B) (2004). https://sites.ed.gov/idea/
• Lent, R. W., Brown, S. D., & Hackett, G. (1994). Toward a unifying social cognitive theory of career and academic interest, choice, and performance. Journal of Vocational Behavior, 45(1), 79–122. https://doi.org/10.1006/jvbe.1994.1027
• Mabe, P. A., & West, S. C. (1982). Validity of self-evaluation of ability: A review and meta-analysis. Journal of Applied Psychology, 67(3), 280–296. https://doi.org/10.1037/0021-9010.67.3.280
• Mau, W.-C. (2001). Test review: Ability Explorer. Measurement and Evaluation in Counseling and Development, 34(3), 187–190. https://doi.org/10.1080/07481756.2001.12069034
• Mau, W.-C. (2009). Ability Explorer. In E. A. Whitfield, R. W. Feller, & C. Wood (Eds.), A counselor’s guide to career assessment instruments (5th ed., pp. 82–88). National Career Development Association.
• Mau, W.-C. (2012). Ability Explorer. In C. Wood & D. G. Hays (Eds.), A counselor’s guide to career assessment instruments (6th ed., pp. 116–124). National Career Development Association.
• Melson, B., Hale, R., & Foster, M. (2013). The importance and challenge of ability assessment. Career Planning and Adult Development Journal, 29(4), 98–113.
• Parsons, F. (1909). Choosing a vocation. Houghton Mifflin.
• Rajewski, J. (2002). Career assessment for adolescents with mild disabilities: Critical concerns for transition planning. Career Development for Exceptional Individuals, 25(1), 73–95. https://doi.org/10.1177/088572880202500106
• Scannell, D. P., Haugh, O. M., Schild, A. H., & Ulmer, G. (1976). Tests of achievement and proficiency. Riverside Publishing.
• U.S. Department of Education, National Center for Education Statistics. (2014). The condition of education 2014: Immediate transition to college (NCES 2014–083). https://nces.ed.gov/fastfacts/display.asp?id=51
• U.S. Department of Labor, Employment and Training Administration. (1979). Guide for occupational exploration. Government Printing Office.

13. Items of the Scale