Validation of the Single-item Sleep Quality Scale

The single-item sleep quality scale (SQS) allows patients to provide a self-assessment of sleep quality over a 7-day recall period without significant additional burden. However, the SQS has not yet been utilized or validated in patients with spine pathologies. The main purpose of this study is to cross-culturally adapt the SQS from English to German and Italian and to test its validity in patients with back disorders. The study will be conducted in two stages. The first stage will involve the translation and cross-cultural adaptation of the SQS from English to German and Italian. The second stage will involve the evaluation of the instrument's face, content, and construct validity, reproducibility, and responsiveness in patients with back disorders.