Vulnerability in elderly patients with gastrointestinal cancer – translation, cultural adaptation and validation of the European Portuguese version of the Vulnerable Elders Survey (VES-13)

BACKGROUND: “Vulnerable Elders Survey” (VES-13) is a questionnaire accurate in predicting functional decline and highly correlated with comprehensive geriatric assessment in identifying vulnerable elderly. The purpose of this study was to translate, cultural adapt and validate the first Portuguese cross-cultural version of VES-13 and to estimate the prevalence of vulnerability in Portuguese elderly gastrointestinal (GI) cancer patients. METHODS: VES-13 European Portuguese translation and cultural adaptation was developed according to internationally accepted guidelines. Test-retest reliability and internal consistency were assessed by calculating the Kappa statistic and by analyzing the inter-item and item-total correlation matrices and calculation of Cronbach’s alpha coefficients, respectively. Construct and criterion validity was assessed by Spearman’s correlation coefficient between VES-13 and each EQ-5D-5 L dimension, clinical judgment and performance status. RESULTS: The translated and culturally adapted version of VES-13 revealed high test-retest reliability (test-retest Kappa ≥ 0.612; p < 0.001) in the pilot study (n = 22). For the validation phase 206 patients with GI cancer were recruited (median age: 73 years; colo-rectal cancer: 63 %). Criterion validity was confirmed by adequate correlations between VES-13 and clinical judgment of vulnerability, ECOG and KPS scores. Construct validity was confirmed by moderate correlations with most of EQ-5D-5 L dimensions. Cronbach’s alpha of the questionnaire was 0.848. The estimated prevalence of vulnerability is 50 % (CI95% 0.43-0.56). CONCLUSIONS: The European Portuguese version of VES-13 is a valid and reliable approach to screening elderly cancer patients for geriatric needs. In our setting, one in two elderly patients was likely to be vulnerable or frail which stresses the importance of their correct identification to better inform cancer management. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12885-015-1739-2) contains supplementary material, which is available to authorized users.