Translation and linguistic validation of the FACT-EGFRI-18 quality of life instrument from English into Dutch.

PURPOSE The Functional Assessment of Cancer Therapy-Epidermal Growth Factor Receptor Inhibitor 18 (FACT-EGFRI-18) is a patient-reported outcomes questionnaire developed to assess the effect of EGFRI on patients. The FACT-EGFR-18 was translated into Dutch and evaluated in order to document that the translation adequately captures the concepts of the original English-language version of the questionnaire and is readily understood by subjects in the target population. METHOD Translation of the FACT-EGFRI-18 from English to Dutch was accomplished by employing the Functional Assessment of Chronic Illness Therapy (FACIT) multilingual translation methodology. Ten native-speaking residents of the target country who reported EGFRI associated dermatological adverse events (dAEs) were asked to review the translation of the harmonized FACT-EGFRI-18. RESULTS Participants generally found the Dutch FACT-EGFRI-18 easy to understand and complete. In addition, the translation retained the original meaning of the FACT-EGFRI-18 items and instructions. Based on the results of the cognitive debriefing interviews, no changes to improve clarity and comprehension of translations were identified. CONCLUSIONS The Dutch FACT-EGFRI-18 demonstrates content validity and linguistic validity, and was found conceptually equivalent to its English source, thus confirming linguistic validation. The results suggest that the Dutch FACT-EGFRI-18 can be applied to measure dAE related health related quality of life in Dutch-speaking patients undergoing EGFRI therapy. Formal validation of the Dutch FACT-EGFRI-18 is ongoing.