Alliance and Suicide Prevention Lab

Graduate Students

Undergraduate Honors Thesis Projects

Assessor effects on the evaluation of the WISC-III

By Sherecce Fields, Ph.D.

A Masters Thesis Defended Spring 2004

Project Overview

There have been many theories about cultural differences found between groups on intelligence test scores. The main debate has been between those in favor of a genetic explanation versus those in favor of a more environmental one. When considering environmental influences, one explanation has been that there could be differential effects due to the assessor. Although there have been several studies that have considered this possibility, the results are inconclusive. The current study attempted to tease apart the assessor effects by focusing on biases in the assessor alone and by eliminating effects from the test taker. The study is an experimental design where participants were randomly assigned a WISC-III protocol of members of different ethnic groups. It was hypothesized that different groups may score these IQ tests differentially depending on the race/ethnicity of the person who was assessed. Results showed that when given identical protocols, participants scored African American protocols lower than Caucasian American protocols in both high and average IQ conditions. Clinical implications of these results are discussed.