Cross-Cultural Adaptation and Validation of the Italian Version of SWAL-QOL.

Abstract

The aim of the study was to evaluate the reliability and validity of the Italian SWAL-QOL (I-SWAL-QOL). The study consisted of five phases: item generation, reliability analysis, normative data generation, validity analysis, and responsiveness analysis. The item generation phase followed the five-step, cross-cultural, adaptation process of translation and back-translation. A group of 92 dysphagic patients was enrolled for the internal consistency analysis. Seventy-eight patients completed the I-SWAL-QOL twice, 2weeks apart, for test-retest reliability analysis. A group of 200 asymptomatic subjects completed the I-SWAL-QOL for normative data generation. I-SWAL-QOL scores obtained by both the group of dysphagic subjects and asymptomatic ones were compared for validity analysis. I-SWAL-QOL scores were correlated with SF-36 scores in 67 patients with dysphagia for concurrent validity analysis. Finally, I-SWAL-QOL scores obtained in a group of 30 dysphagic patients before and after successful rehabilitation treatment were compared for responsiveness analysis. All the enrolled patients managed to complete the I-SWAL-QOL without needing any assistance, within 20min. Internal consistency was acceptable for all I-SWAL-QOL subscales (α>0.70). Test-retest reliability was also satisfactory for all subscales (ICC>0.7). A significant difference between the dysphagic group and the control group was found in all I-SWAL-QOL subscales (p<0.05). Mild to moderate correlations between I-SWAL-QOL and SF-36 subscales were observed. I-SWAL-QOL scores obtained in the pre-treatment condition were significantly lower than those obtained after swallowing rehabilitation. I-SWAL-QOL is reliable, valid, responsive to changes in QOL, and recommended for clinical practice and outcome research.