The psychological tests can be classified into two categories:
1. On the basis of the nature of testing:
All behaviour cannot be tested or experienced. People may have language difficulties or may be too young or may not be used for testing situation.
Hence, psychologists have developed different testing methods. These are divided into standardised tests and non-testing methods.
Standardised tests, as the name suggests, are standardised which can be used by different people by following the instructions given in the manual. These are the valid tests which give objective results, without giving room for subjective influences.
Non-testing method of testing: This is a type of testing without using any standardised tests. These methods include: (a) observation (b) interview (c) sociometry (d) case study (e) rating scales (f) behavioural analysis (g) anecdotal method (h) cumulative records study.
2. On the basis of functions of tests:
Many numbers of tests have been developed by psychologists, because human psyche consists of many factors. The behaviour of an individual is influenced by so many factors. Hence, different tests are necessary to measure all these factors. The important among them are:
1. Intelligence tests
2. Personality tests
3. Interest inventories
4. Aptitude tests
5. Attitude tests
6. Tests of educational achievement
7. Value tests
In each category there are so many tests to suit the age, sex, need of the tester, purpose of testing, etc.