The reliability of the German version of the Barthel-Index and the development of a postal and telephone version for the application on stroke patients

Background and purposes: Aim of the study was to translate the original version of the Barthel-Index (BI) into German and to investigate the reliability of the German version. In addition, a German version of the BI for postal and telephone use was developed. Methods: Data were collected in four neurological hospitals in Germany. The translation of the BI followed the protocol of the Medical Outcomes Trust. The interrater reliability of the German version of the BI was investigated in 72 patients after acute stroke. The reliability of the postal and telephone version of the BI was compared with face-to-face interview in 147 patients three months after stroke. Reliability was assessed using simple weighted kappa-statistics. Results: The interrater reliability of the German version of the BI was excellent (mean kappa 0.93). The mean kappa coefficient was 0.79 for the postal version of the BI and 0.80 for the telephone version. Thus, the agreement between the postal and the telephone administration of the BI compared to the face-to-face interview was substantial to excellent. Conclusions: Our study published the first German version of the BI which was investigated for interrater reliability in a standardized way. The development of a postal and a telephone version allows the widespread use of the German BI for the follow up of stroke patients in different access paths.