Braun T.1,2, Gasser C.3,4, Göbel A.5, Marks D.6, Grüneberg C.1
1Hochschule für Gesundheit, Department of Applied Health Sciences, Bochum, Germany, 2University of Cologne, Medical Faculty, Cologne, Germany, 3Kantonsspital Aarau, Aarau, Switzerland, 4SRH Hochschule für Gesundheit Gera, Gera, Germany, 5Kantonsspital Winterthur, Winterthur, Switzerland, 6Rehaklinik Zihlschlacht, Physioherapy, Zihlschlacht, Switzerland
Background: Mobility is an important outcome in stroke rehabilitation, as approximately two out of three stroke survivors experience significant mobility limitations [Friedman 1990, Jørgensen 1995]. There are not many measurement instruments of post-stroke mobility available for the acute setting [van Bloemendaal 2012]. The de Morton Mobility Index (DEMMI) is an established and unidimensional measurement instrument of mobility in acute older medical patients [de Morton 2008, Braun 2015] that might be attractive to use in acute stroke rehabilitation.
Purpose: To analyse the internal consistency reliability and construct validity of the DEMMI in patients with acute stroke.
Methods: A set of outcomes of physical functioning and mobility was performed by physical therapists with patients admitted to a stroke unit within the first seven days after admission.
Cronbachs alpha was calculated for internal consistency reliability. Construct validity was assessed by testing hypotheses about expected correlations between the DEMMI and other constructs (e.g. mobility, ambulation, balance) and expected differences on DEMMI scores between groups defined on mobility related characteristics.
Results: The DEMMI was assessed in 141 patients with stroke immediately after the stroke event (2.7 ± 1.6 days). The mean age of participants was 71 ± 15 years, 57% were male, 91% had an ischemic stroke, the median National Institutes of Health Stroke Scale score was 3 points (interquartile range: 2-8) and 60% were ambulatory.
Cronbachs alpha was 0.94. Construct validity was supported by confirmation of 100% of the hypothesized correlations and known-group differences.
Conclusion(s): These results indicate excellent [Terwee 2007] internal consistency and construct validity of the DEMMI in acute stroke rehabilitation. Generalizability of results is limited as patients with severe aphasia and cognitive impairment were excluded from the mobility measures and the limited validity of the reference assessments.
Other measurement properties such as unidimensionality, intra- and inter-rater reliability, responsiveness and interpretability of the DEMMI in patients with acute stroke have not been examined.
Implications: Further studies on the DEMMI in stroke rehabilitation should be conducted. In the light of evidence for the DEMMI in acute older medical patients [de Morton 2008, Sommers 2016, New 2016] and the results of this study, the DEMMI can be considered to assess post-stroke mobility in a stroke unit setting.
Funding acknowledgements: None.
Topic: Neurology: stroke
Ethics approval: Swiss Ethics Committees on research involving humans (Ethikkommission Nordwest- und Zentralschweiz EKNZ; registration number: 2016-00190).
All authors, affiliations and abstracts have been published as submitted.
