German translation, cross-cultural adaptation and diagnostic test accuracy of three frailty screening tools

Abstract

Routine screening for frailty could be used to timely identify older people with increased vulnerability und corresponding medical needs. The aim of this study was the translation and cross-cultural adaptation of the PRISMA-7 questionnaire, the FRAIL scale and the Groningen Frailty Indicator (GFI) into the German language as well as apreliminary analysis of the diagnostic test accuracy of these instruments used to screen for frailty. A diagnostic cross-sectional study was performed. The instrument translation into German followed astandardized process. Prefinal versions were clinically tested on older adults who gave structured in-depth feedback on the scales in order to compile afinal revision of the German language scale versions. For the analysis of diagnostic test accuracy (criterion validity), PRISMA-7, FRAIL scale and GFI were considered the index tests. Two reference tests were applied to assess frailty, either based on Fried's model of aPhysical Frailty Phenotype or on the model of deficit accumulation, expressed in aFrailty Index. Prefinal versions of the German translations of each instrument were produced and completed by 52older participants (mean age: 73± 6 years). Some minor issues concerning comprehensibility and semantics of the scales were identified and resolved. Using the Physical Frailty Phenotype (frailty prevalence: 4%) criteria as areference standard, the accuracy of the instruments was excellent (area under the curve AUC >0.90). Taking the Frailty Index (frailty prevalence: 23%) as the reference standard, the accuracy was good (AUC between 0.73 and 0.88). German language versions of PRISMA-7, FRAIL scale and GFI have been established and preliminary results indicate sufficient diagnostic test accuracy that needs to be further established.