Monitoring of physical activity after stroke: a systematic review of accelerometry-based measures.

Objective: To assess the clinimetric properties and clinical applicability of different accelerometry-based measurement techniques in persons with stroke.

Data Sources: A systematic search of literature was performed using a specific search strategy by means of different electronic databases until October 2008 (PubMed, EMBASE, CINAHL, Cochrane Library of Clinical Trials).

Study Selection: A first selection was made by means of title and abstract. A second selection was performed by means of predefined inclusion criteria: (1) accelerometry in stroke population, (2) application of accelerometry in patients with stroke including clinimetric properties. The exclusion criteria were (1) dysphagia, (2) new engineering techniques or software alterations, (3) secondary sources, and (4) Case studies.

Data Extraction: The clinimetric properties and applicability of accelerometry were described based on the included publications.

Data Synthesis: Twenty-five articles (4 randomized controlled trials) were included. The information of the publications was divided into (1) gait, cadence, and ambulatory activity; (2) upper-extremity activity; and (3) topics related to stroke other than upper or lower extremity. Accelerometry was shown to be valid and had good test-retest reliability in a large number of settings. Numerous studies demonstrated correlations between accelerometry and common stroke scales. Trunk movements were measured as an outcome of disturbed gait. The vertical asymmetry index especially was able to differentiate between persons with stroke and healthy controls. Persons with stroke showed less ambulatory activity, measured as steps per day, than sedentary controls. Triaxial accelerometry was able to distinguish between varying activity levels. Upper-extremity use was lesser in persons with stroke. It was impossible to calculate a minimal clinical difference for arm use by a uniaxial accelerometer. Evidence was presented that finger-tapping and sit-to-stand measured by accelerometers could be used to define recovery from stroke.

Conclusions: The literature concerning accelerometry incorporated into stroke research is young, limiting the ability to draw consistent conclusions. Nonetheless, the available evidence suggests that accelerometers yield valid and reliable data about the physical activity of patients with stroke. Future research is necessary to investigate clinimetric properties like predictive value and responsiveness further before implementing accelerometry in clinical trials as an outcome for change.