Personality questionnaires based on self-assessment began evolving are still the most common instruments in personality psychology & assessment. They provide research economics, and are efficient in regards of the time and effort. In some cases, self-assessment is often the only access to a test person. Even though questionnaires are nowadays being tested with scientific methods and are improved in terms of performance data and robustness, certain problems of self-assessment questionnaires remain:
- Systematic biases regarding retrospective questions about experiences and frequencies
- Subjectivity of test persons
- Dependency on context (e.g., purpose of test)
- Tendencies to social desirability (e.g., in the hiring process)
- Tendencies to the middle or extreme by answers to questionnaire items
- Ambiguity of understanding questionnaire items
This is why nonverbal tests are getting more popular. Handwriting psychology, represents a nonverbal testing system for personality traits. There are certain advantages of this method for psychological assessment:
- Large number of personality traits can be assessed in one procedure.
- Social desirability is totally excluded.
- Writing by hand is a normal and natural activity for most people that excludes the influence of
- testing situations.
- Handwriting samples can be obtained independently of time, place, and physical presence of the
- test persons.
- Psychological development of test persons can be assessed when several handwriting samples
- produced in different ages are available.
- The language of the handwriting sample (valid for European languages) has no influence on the
- evaluation process.
The aim is to develop handwriting psychology at the level of a mature psychometric instrument with regard to the standard requirements of psycho-diagnostic methods which are objectivity, reliability and validity:
Objectivity of Handwriting Analysis
Objectivity of a method/instrument ensures that the results do not depend on the person who performs the test. For handwriting psychology it includes the evaluation of handwriting signs and evaluation of personality structures (traits). The evaluation of handwriting is ensured by formal, algorithmic-like procedure of evaluation for manual procedure and by the use of computer-aided methods, where applicable.
The evaluation of personality traits is ensured by the application of computer-aided tools (HSDetect).
Reliability of Handwriting Analysis
Reliability of a method/instrument ensures that the results are stable and do not change by the repeating of the test.
Reliability is, in particular, verified by expert concordance experiments (statistical verification of expert agreement on evaluation of handwriting signs and personality traits ) and ring trails for handwriting analysis (method to proof that the statements made by handwriting experts are reliably identifiable and are determinable with an acceptable level of precision).
Validity of Handwriting Analysis
To be valid a method/instrument must measure what it is supposed to be measure, for handwriting psychology that is personality structures. We are looking at different subdivisions of validity: construct validity, content validity, and criterion validity.
Validation is done by checking of handwriting psychology against well-validated and generally accepted psychometric tests and comparison it with statistically well-agreed expert opinions.