Reliability and Validity of The Belbin Model
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
Internal 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 of 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.
Dulewicz V., (1995) "A validation of Belbin's team roles from 16PF and OPQ using bosses' ratings of competence", Journal of Occupational and Organizational Psychology, Vol 68, pp. 81-99.
Fisher, S. G., Hunter, T.A. and Macrosson, W.D.K. (1998), "The structure of Belbin's team roles", Journal of Occupational and Organizational Psychology, Vol. 71, pp. 283-8.