Further Development of the Big Store Multiple Errands Test

The Multiple Errands Test (MET) is a tool for assessing the effects of executive function impairments, common among those with acquired brain injury, on everyday life function. The objective of this study was to further establish inter-rater reliability and explore known group validity of the Big-Store MET in distinguishing between adults with an ABI and matched healthy controls, and to explore the effects of environmental factors on Big-Store MET performance. Participants (<i>n</i> = 5 community-dwelling people with ABI, <i>n</i> = 4 healthy controls) were administered the Big Store MET by one of two trained raters. Inter-rater reliability was examined using intra-class correlation coefficients. Known-group validity was examined using Cohen's d effect size, and the effects of environmental load and familiarity on performance were examined descriptively. The results showed the inter-rater reliability was very high for all MET performance scores (ICC =0.74-1.00). Effect sizes for known group validity were moderate to large (<i>d</i> = 0.48-1.06) on five of six performance scores on the MET. Descriptively, control participants performance was better with higher store familiarity and lower environmental load whereas the opposite was found for participants with ABI. This research suggests the Big-Store MET may be a clinically useful tool and highlights the importance of further development.