Evaluation of psychometric properties of the German Hospital Survey on Patient Safety Culture and its potential for cross-cultural comparisons: a cross-sectional study

OBJECTIVE To study the psychometric characteristics of German version of the Hospital Survey on Patient Safety Culture and to compare its dimensionality to other language versions in order to understand the instrument's potential for cross-national studies. DESIGN Cross-sectional multicentre study to establish psychometric properties of German version of the survey instrument. SETTING 73 units from 37 departments of two German university hospitals. PARTICIPANTS Clinical personnel (n=995 responses, response rate 39.6%). PRIMARY AND SECONDARY OUTCOME MEASURES Psychometric properties (eg, model fit, internal consistency, construct validity) of the instrument and comparison of dimensionality across different language translations. RESULTS The instrument demonstrated acceptable to good internal consistency (Cronbach's alpha 0.64-0.88). Confirmatory factor analysis of the original 12-factor model resulted in marginally satisfactory model fit (root mean square error of approximation (RMSEA)=0.05; standardised root mean residual (SRMR)=0.05; comparative fit index (CFI)=0.90; goodness of fit index (GFI)=0.88; Tucker-Lewis Index (TLI)=0.88). Exploratory factor analysis resulted in an alternative eight-factor model with good model fit (RMSEA=0.05; SRMR=0.05; CFI=0.95; GFI=0.91; TLI=0.94) and good internal consistency (Cronbach's alpha 0.73-0.87) and construct validity. Analysis of the dimensionality compared with models from 10 other language versions revealed eight dimensions with relatively stable composition and appearance across different versions and four dimensions requiring further improvement. CONCLUSIONS The German version of Hospital Survey on Patient Safety Culture demonstrated satisfactory psychometric properties for use in German hospitals. However, our comparison of instrument dimensionality across different language versions indicates limitations concerning cross-national studies. Results of this study can be considered in interpreting findings across national contexts, in further refinement of the instrument for cross-national studies and in better understanding the various facets and dimensions of patient safety culture.