An instrument to measure mobile shower commode usability: the eMAST 1.0

Purpose The purpose of this paper is to present a preliminary psychometric evaluation of the electronic mobile shower commode assessment tool (eMAST) 1.0. Design/methodology/approach A cross-sectional validation study was undertaken with 32 adults with spinal cord injury (SCI), aged 18 years or older, who use mobile shower commodes for toileting and/or showering. The eMAST 1.0, Quebec user evaluation of satisfaction with assistive technology, Version 2.0 (QUEST 2.0), and modified system usability scale (SUS) were administered online via SurveyMonkey. The eMAST 1.0 was re-administered approximately seven days later. Psychometric properties of internal consistency, test-retest reliability, and convergent validity were assessed. Findings As hypothesised, the eMAST 1.0 demonstrated strong internal consistency (Cronbach’s α=0.73, N=32); acceptable test-retest reliability (intra-class coefficient (3, 1)=0.75 (0.53-0.88, 95 per cent confidence interval) (n=27)); and strong, positive correlations with the QUEST 2.0’s devices subscale and modified SUS (Pearson’s correlation coefficients 0.70 and 0.63, respectively). Research limitations/implications The sample was not fully representative of Australian data in terms of gender, or state of residence, but was representative in terms of SCI level. Age data were not assessed. The sample size was small but adequate for a preliminary psychometric evaluation. Originality/value The preliminary psychometric evaluation indicates the eMAST 1.0 is a valid and reliable instrument that measures usability of MSCs for adults with SCI. It may be useful for exploring relationships between usability and satisfaction of MSCs.