Reliability of an Adapted Version of the Modified Six Elements Test as a Measure of Executive Function

The Modified Six Elements Test (MSET) is used to examine executive deficits—more specifically, planning deficits. This study investigates the reliability of an adapted version of the MSET and proposes a novel scoring method. Two parallel versions of the adapted MSET were administered in 60 healthy participants in a counterbalanced order. Test–retest and parallel-form reliability were examined using intraclass correlation coefficients, Bland-Altman analyses, standard errors of measurement, and smallest real differences, representing clinically relevant changes over time. Moreover, the ecological validity of the adapted MSET was evaluated using the Executive Function Index, a self-rating questionnaire measuring everyday executive performance. No systematic differences between the test occasions were present, and the adapted MSET including the proposed scoring method was capable of detecting real clinical changes. Intraclass correlations for the test–retest and parallel-form reliability were modest, and the variability between the test scores was high. The nonsignificant correlations with the Executive Function Index did not confirm the previously established ecological validity of the MSET. We show that both parallel versions of the test are clinically equivalent and can be used to measure executive function over the course of time without task-specific learning effects.