Related Experiment Video
Updated: Jul 20, 2026

Use of a Video Scoring Anchor for Rapid Serial Assessment of Social Communication in Toddlers
Published on: March 14, 2018
Rater bias and the measurement of support needs
Roma Guscia1, Julia Harries, Neil Kirby
1Department of Psychology, University of Adelaide, Australia. roma.guscia@psychology.adelaide.edu.au
Background:
The development and use of support need instruments for funding disability services is a relatively recent initiative. Although the use of these measures appears at face value to provide an objective measure of support needs, little is known about their psychometric properties, particularly with respect to rater bias and purpose of assessment. A measure of support that has been developed in Australia to provide estimates of service needs and associated funding is the Service Need Assessment Profile (SNAP).
Method:
This study investigated whether SNAP scores obtained for different assessment purposes - research and funding - are affected by rater bias, by comparing SNAP to 3 other measures of support from 29 people with intellectual disabilities.
Results:
We found that SNAP scores completed for funding purposes showed an individual's support needs to be much greater than comparison scores on both SNAP and the 3 other measures obtained for research purposes.
Conclusions:
Our results suggest that support measures such as SNAP may significantly overestimate support needs when raters know the assessment is being used for funding purposes.
Related Concept Videos
Bias
In statistics, a sampling bias is created when a sample is collected from a population, and some members of the population are not as likely to be chosen as others (remember, each member...
Surveys
Bias in Epidemiological Studies
Motivational Bias
Confirmation Biases
Self-Serving Bias
