Introduction
Psychology is the scientific study of human behavior and mental functions. The professionals involved in this field are referred to as psychologists. The term test refers to a form of examination with an objective to determine an outcome. Therefore, a psychological test is a scientific examination of human behavior and mental construct in a given environment.
Psychological testing is a field of study in which cognitive constructs are assessed through behavioral sampling. It may focus on the emotional functioning and cognition of an individual. The whole process of psychological testing is known as psychometrics. It involves the observation of individuals performing pre- prescribed tasks. The responses of the individuals are summarized on statistical tables which are later analyzed (Watson, 1919).
There are several categories of psychological testing. These are:
Personality test
This assesses the basic styles of personality and is frequently used in forensic settings. There are several personality tests, two of which are the Rorschach otherwise knownw as the “the inkblot test”. This test constitutes a number of inkblot cards from which one gives image descriptions and feelings experienced while looking at the blots. Another is the Minnesota Multiphasic Personality Inventory (MMPI). This type of personality test uses a large number of “yes” and “no” objectives to collect data (Richmond, 2010)
Neuropsychological test
This is concerned with cognitive functioning. It examines the deficiencies in the ability to think, and reason that might stem from brain disorders or disease (Richmond, 2010).
Intelligence test
This attempts to assess one’s basic ability to conceptualize the environment around him or her and use it to enhance the quality of his or her life. This test does not have cultural inclination and is an assessment of potentiality. This means it has nothing to do with what has already been learnt (Richmond, 2010).
Occupational test
The test tries to assess one’s interest and matches it with the interest of other individuals in a field of focus. When one’s occupational interest matches those of others already in the same field, it can safely be concluded that the person qualifies to join the rest (Richmond, 2010).
Achievement and aptitude test
It is mainly used in educational and employment settings. It assesses how much an individual knows about a given line of knowledge. For instance, it may test one’s knowledge ability of a language or subject of concern. It can also be used to test the ability to master information in a given area (Richmond, 2010).
The concepts of reliability and validity
Reliability is a situation where the assessment process yields results that are consistent, especially after several assessments are carried out. Reliability has three qualities. There is inter-item reliability in which tools are used in multiple ways to measure one concept. In test-retest reliability a tool of measurement is used several times. Reliability here is measured by the ability to achieve a consistent outcome after several tests. Finally, in inter-observer reliability several observers use a similar tool of measurement to assess a given situation. The reliability is found in the ability of the observers to achieve similar outcomes.
Validity can be defined as the accuracy and relevancy of a material or an object as relate to what it is intended for. There exist several validity forms. Content validity refers to the ability of a testing tool to sample a wide range of components that constitute a construct. Construct validity refers to the ability of a psychological tool to assess the behavioral construct it is intended to assess. Criterion-related validity is the ability of a given tool to assess performance using a specific criterion.
There is no close relationship between reliability and validity. A measurement can either have validity and reliability both being high and also we can have another measurement which has high validity and low reliability and the converse. In both reliability and validity either can produce inconsistent results which lack accuracy (Laura, 1997: Yu, 2005).
How reliability and validity affect the field of psychological testing
In the case of repeated measurements consistent results may not be achieved. Students may sit for a test at different times and occasions. When the same students are given the same exams they may score higher than before because they are used to the same test questions. In cases where reliability is important it may not satisfy the conditions for validity. Reliability may reflect consistency of an outcome but the outcome can be consistently wrong.
Varied reliability indices may create confusion to the users. Content validity may not give reliable information on a particular measurement, for example, the field of engineering is wide. It is therefore difficult to administer an assessment that covers the whole area of engineering to prove an individual is sufficiently knowledgeable in the field (Laura, 1997).
Conclusion
Psychological testing involves the use of reliability and validity concepts in trying to scientifically study the behavior and cognition of human beings. Reliability and validity may not be fully efficient in psychometrics however they give relevant outcomes that can be used in the context of their intended tasks.
Psychological testing is rather qualitative than quantitative in nature. It seeks to bring out what kind of constructs lie deep in the human mind and the circumstances under which they exist. The circumstances can either be traced in from the past or current situation of an individual and some times may either be internally or externally generated (Laura, 1997: Richmond, 2010).
Reference
Laura, A. (1997). Reliability and Validity: What is the Difference? Web.
Richmond, L. (2010). A guide to Psychology and its Practice: San Francisco. Web.
Watson, B. (1919). Psychology from the Standpoint of Behaviorist. The John Hopkins University. Web.
Yu, C. (2005). Reliability and Validity: Cognitive Psychology. Web.