Inter-rater and Intra-Rater Reliability Test with Goodenough-Harris Drawing Test

Abstract

Introduction: There are various methods to measure intelligence in children, one of them is by drawing method. Goodenough-Harris Drawing Test (GHDT) is the first cognitive measurement tool developed based on drawing. Giving quantitative scores in drawing methods has been a challenging task, especially in controlling the level of subjectivity. It requires psychometric reliability evidence to make sure the result is free from bias. Methods: Drawings of 799 children (kindegarten/4 to 6 y.o= 412, primary school/7 to 9 y.o= 387 ; boys= 388, girls= 411) were examined to investigate inter-rater and intra-rater reliability in GHDT scoring. Data are scored by two raters who have been given special training on the scoring system based on the manual book. Pearson correlation is used to analyzed drawing reliability. Results: Significant correlation between the scores of two rates were 0.840 (p<.001) for the man drawing, and 0.844 (p<.001) for the woman drawing. In addition, intra-rater reliability ranged from 0.880 to 0.963. Conclusion: The study showed that GHDT has a high-reliability score by raters who trained based on a manual book GHDT scoring system. In addition, these results also showed scoring criteria were applied consistently.