Feasibility and Validity of the Mobile Measurement of Spatial Attention and Working Memory in Individuals with Stroke

Research Objectives: We developed a mobile phone-based spatial attention and working memory testing (mSAM) to enable brief, repeated, and portable measurements of spatial attention and working memory. This study evaluated the adherence and psychometric properties of mSAM in community-dwelling individuals with stroke.

Design: We assessed adherence, learning effect, test-retest reliability, convergent and divergent validity against standard neuropsychological tests, and criterion validity against the Wechsler Memory Scale-III Spatial Span. Participants who used smartphones completed mSAM twice daily for 14 days. Participants also completed standard neuropsychological tests during a lab visit.

Setting: Home and Community

Participants: 20 participants with mild-to-moderate chronic stroke (median age: 55.5; 70% ischemic stroke; 40% female; 55% black)

Interventions: Not applicable

Main Outcome Measures: mSAM forward and backward trials assessed spatial attention and working memory, respectively, through a game-like environment, where participants observed and recalled increasingly complex pattern sequences of stimuli presented to them. Standard neuropsychological tests measured a broader range of cognitive domains, including attention/working memory, episodic memory, visuospatial function, executive function, processing speed, expressive language, and receptive language.

Results: Overall mean-level adherence to mSAM forward and backward trials was 81% and 79%, respectively. While performance improved over the 14-day study period (i.e., learning effect), moderate test-retest reliability was observed, with ICC values of 0.54 and 0.55 for forward and backward trials, respectively. Additionally, moderate correlations were found between mSAM and standard neuropsychological tests, encompassing attention/working memory (r=0.71, p<0.001; r=0.78, p< 0.001) and processing speed (r=0.46, p=0.043; r=0.47, p=0.038) for both trials, and executive function and visuospatial function for the backward trial (r=0.49, p=0.028; r=0.46, p=0.043). The Bland-Altman analysis showed good agreement between Wechsler Memory Scale-III Spatial Span and mSAM, with the mean difference and the 95% confidence interval for the forward and backward trials being 2.9 [-11.2, 17.0] and 1.4 [-15.5, 18.2], respectively, suggesting satisfactory criterion validity of mSAM for measuring spatial attention and working memory.

Conclusions: mSAM shows promise as a feasible and ecologically validated method for testing of spatial attention and working memory in individuals with mild-to-moderate stroke. Future research should test the acceptability and potential challenges of using mSAM as outcome measures in clinical trials.

Author(s) Disclosures: Fong has served as a contractor for Isaac Ray Forensic Group and Michigan Avenue Neuropsychologists. Metts has an ownership interest in Infinite Arms. Hu has a stockholder interest in Tencent Holdings Limited.