title: Assessing self-management in patients with diabetes mellitus type 2 in Germany: validation of a German version of the Summary of Diabetes Self-Care Activities measure (SDSCA-G).
abstract: BACKGROUND
  One of the most widely used self-reporting tools assessing diabetes self-management in English is the Summary of Diabetes Self-Care Activities (SDSCA) measure. To date there is no psychometric validated instrument in German to assess self-management in patients with diabetes mellitus. Therefore, this study aimed to translate the SDSCA into German and examine its psychometric properties.
  
  
  METHODS
  The English version of the SDSCA was translated into German following the guidelines for cultural adaptation. The German version of the SDSCA (SDSCA-G) was administered to a random sample of 315 patients with diabetes mellitus type 2. Reliability was analyzed using Cronbach's alpha coefficient and item characteristics were assessed. Exploratory and confirmatory factor analysis (EFA and CFA) were carried out to explore the construct validity. A multivariable linear regression model was used to identify the influence of predictor variables on the SDSCA-G sum score.
  
  
  RESULTS
  The Cronbach's alpha for the SDSCA-G (all items) was α = 0.618 and an acceptable correlation between the SDSCA-G and Self-management Diabetes Mellitus-Questionnaire (SDQ) (ρ = 0.664) was identified. The EFA suggested a four factor construct as did the postulated model. The CFA showed the goodness of fit of the SDSCA-G. However, item 4 was found to be problematic regarding the analysis of psychometric properties. The omission of item 4 yielded an increase in Cronbach's alpha (α = 0.631) and improvements of the factor structure and model fit. No statistically significant influences of predictor variables on the SDSCA-G sum score were observed.
  
  
  CONCLUSIONS
  The revised German version of the SDSCA (SDSCA-G) is a reliable and valid tool assessing self-management in adults with type 2 diabetes in Germany.
authors.affiliation: Department of General Practice and Health Services Research, University Hospital Heidelberg, Voßstr. 2, Geb. 37, D-69115, Heidelberg, Germany. martina.kamradt@med.uni-heidelberg.de.
authors.forename: Martina
authors.initials: M
authors.lastname: Kamradt
authors.affiliation: Department of General Practice and Health Services Research, University Hospital Heidelberg, Voßstr. 2, Geb. 37, D-69115, Heidelberg, Germany. kayvan.bozorgmehr@med.uni-heidelberg.de.
authors.forename: Kayvan
authors.initials: K
authors.lastname: Bozorgmehr
authors.affiliation: Department of Medical Biometry; Institute of Medical Biometry and Informatics, University Hospital Heidelberg, Im Neuenheimer Feld 305, D-69120, Heidelberg, Germany. krisam@imbi.uni-heidelberg.de.
authors.forename: Johannes
authors.initials: J
authors.lastname: Krisam
authors.affiliation: Department of General Practice and Health Services Research, University Hospital Heidelberg, Voßstr. 2, Geb. 37, D-69115, Heidelberg, Germany. tobias.freund@med.uni-heidelberg.de.
authors.forename: Tobias
authors.initials: T
authors.lastname: Freund
authors.affiliation: Department of General Practice and Health Services Research, University Hospital Heidelberg, Voßstr. 2, Geb. 37, D-69115, Heidelberg, Germany. marion.kiel@med.uni-heidelberg.de.
authors.forename: Marion
authors.initials: M
authors.lastname: Kiel
authors.affiliation: Department of General Practice and Health Services Research, University Hospital Heidelberg, Voßstr. 2, Geb. 37, D-69115, Heidelberg, Germany. markus.qreini@med.uni-heidelberg.de.
authors.forename: Markus
authors.initials: M
authors.lastname: Qreini
authors.affiliation: Department of General Practice and Health Services Research, University Hospital Heidelberg, Voßstr. 2, Geb. 37, D-69115, Heidelberg, Germany. elisabeth.flum@med.uni-heidelberg.de.
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Flum
authors.affiliation: Department of General Practice and Health Services Research, University Hospital Heidelberg, Voßstr. 2, Geb. 37, D-69115, Heidelberg, Germany. sarah.berger@med.uni-heidelberg.de.
authors.forename: Sarah
authors.initials: S
authors.lastname: Berger
authors.affiliation: Genossenschaft Gesundheitsprojekt Mannheim e.G., Liebfrauenstr. 21, D-68259, Mannheim, Germany. werne@besier.info.
authors.forename: Werner
authors.initials: W
authors.lastname: Besier
authors.affiliation: Department of General Practice and Health Services Research, University Hospital Heidelberg, Voßstr. 2, Geb. 37, D-69115, Heidelberg, Germany. joachim.szecsenyi@med.uni-heidelberg.de.
authors.forename: Joachim
authors.initials: J
authors.lastname: Szecsenyi
authors.affiliation: Department of General Practice and Health Services Research, University Hospital Heidelberg, Voßstr. 2, Geb. 37, D-69115, Heidelberg, Germany. dominik.ose@med.uni-heidelberg.de.
authors.forename: Dominik
authors.initials: D
authors.lastname: Ose
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003430:Cross-Sectional Studies; D003924:Diabetes Mellitus, Type 2 / Q000628:therapy*; D005163:Factor Analysis, Statistical; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D011594:Psychometrics; D011788:Quality of Life; D015203:Reproducibility of Results; D012648:Self Care; D057566:Self Report; D011795:Surveys and Questionnaires; D014177:Translations