Reliability & Validity


Defining the terms

Reliability and validity are concepts commonly used in evaluating psychometric tests.

  • Reliability is a measure of the internal consistency of a test
  • Validity is concerned with the strength of the conclusions and inferences drawn

Clusters of behaviour

Roles - no borderInternal consistency is highest where test items are repeated, but this narrows the focus of the test overall. Rather than repeating questions, or introducing items which are virtually identical, Interplace (the program which analyses and produces the Belbin reports) seeks for clusters of related behaviour. For example, the Shaper cluster refers to an individual who is challenging, competitive, hard driving, tough and outspoken. However, that does not mean to say that everyone who is competitive will necessarily be outspoken.


The Full Picture

Most psychometric tests rely on self-reporting. However, the behaviours identified may not correspond with what others observe. The strength of the program, Interplace, rests in its emphasis on construct validity: using multiple sources BELBINUK - IMP Vixof evidence to draw a conclusion. The system’s outputs are designed to take account of the degree of consensus on observed behaviour. Disparities between self-analysis and the perceptions of others can provide valuable leads for action. Formal correlations are, however, difficult to calculate, as those providing feedback are not required to make a fixed number of responses. This is because genuine responses are more easily obtained – and more valuable – when forced choices are avoided.

Remember that the self- and observer assessments feature several different behavioural traits for each Team Role. This is not the case in a psychometric test, where single personality traits are measured. To be a good example of a particular Team Role, an individual would have to demonstrate the cluster of positive traits for that role.


How do I find out MY Team Role preferences?

To find out which of the 9 Belbin Team Roles you have an affinity towards, and which ones you don’t, you need to start by completing a Belbin Self-Perception Inventory.

This is a questionnaire that takes about 20 minutes to complete. A report is automatically generated and sent back to you online. You can add depth and context to your report by asking people who work with you to complete an Observer Assessment. This will help you see not only which roles you prefer, but which ones your colleagues see and value!