Cross-cultural adaptation of the US National Cancer Institute's PRO-CTCAE instrument into Italian for adult cancer patients

Abstract

Introduction: PRO-CTCAE is a patient-reported outcome instrument developed by the US National Cancer Institute to assess symptomatic toxicity (78 symptom terms for females, 75 for males) in patients on cancer clinical trials. Our aim was to translate and cross-culturally validate the PRO-CTCAE instrument into Italian. Methods: Cross-cultural adaptation was conducted in 5 steps, following international guidelines. After forward and back translation with reconciliation, the prefinal version was examined through cognitive debriefing.We planned to enroll 96 adult patients ( pts) at 15 Italian centers, with advanced cancer, having receiving chemo or radiotherapy in the past 6 months. Purposive sampling was used to achieve a balanced sample with respect to age, gender, educational attainment and geographic region. Cognitive debriefing (CD) interviews are conducted to evaluate comprehension, recall, judgment, response mapping and acceptability. Results: Translation - Thirty symptom terms exhibited both literal and semantic equivalence to the original translations, while 76 showed semantic equivalence. For one symptom term, the meaning between the original and the back translation (“Pain in the abdomen (belly)” vs “stomach ache”) differed appreciably. The Expert Committee reviewed all items, and produced the pre-final version of the Italian tool, which was reviewed and approved by US NCI. Cognitive debriefing - To date, 68 pts (40 females, 28 males) have completed CD interviews. The sample (median age 60, 59% female) includes pts from north (46%), central (28%) and southern (26%) Italian regions. A majority had completed only elementary (25%) or secondary (32%) education.With 61 interviews analysed, most pts experienced no difficulties interpreting the items or response choices, and completed the PRO-CTCAE questions with ease. Symptom terms posing the greatest difficulty with comprehension were “pain” (9 pts), “flashing lights before your eyes” (7 pts), “nausea”(6 pts), “bed sores”(5 pts) and “vomiting” (5 pts). Some of these items have undergone revision, and all are being tested in subsequent interview rounds. Conclusions: Preliminary results of this study demonstrate high levels of comprehension and acceptability, and support the conceptual and semantic equivalence to the original, of the Italian language version of PRO-CTCAE. Final results will be available in 3 months. Partially supported by an unrestricted grant from the Fondazione Smith Kline.