The German version of the Functional Walking Categories (FWC): translation and initial validation.

Background: Community ambulation is often affected after a stroke. However, no validated assessment in German to measure community ambulation on a participation level exists. Objectives: The purpose was to translate and cross-culturally adapt the Functional Walking Categories (FWC) into German and to assess its validity and reliability in patients with stroke. Methods: Cross-cultural adaptation guidelines were used for translation. Face and content validity were established with the aid of an expert committee. A pilot study with patients after stroke in a neurological rehabilitation setting checked for concurrent validity using Kendall's tau and reliability using intraclass correlation coefficients. Results: The results indicated that the German version of the FWC has adequate face and content validity. A total of 30 patients (mean age 62 +/- 12.315 years, 56.7% female) participated in the study. The FWC correlated well with the Functional Ambulation Categories (tau-b = 0.783), cadence (tau-b = 0.640), gait velocity (tau-b = 0.628), the comfortable 10-m timed walk (tau-b = -0.629), and the fast 10-m timed walk (tau-b = -0.634). Moderate correlations were found between the FWC and step length (tau-b = 0.483) and the Timed Up and Go (tau-b = -0.520), respectively. Intrarater reliability was moderate (ICC = 0.651) while interrater reliability was excellent (ICC = 0.751) (all correlations p < 0.001). However, the study was designed as pilot study, thus, full psychometric property testing was not possible. Conclusions: The German FWC offers a reasonable tool for measuring community ambulation on participation level. However, a user manual seems to be helpful.