ThyPROpl--The Polish version of the thyroid-specific quality of life questionnaire ThyPRO.

INTRODUCTION Thyroid disorders have a significant impact on patients' quality of life. ThyPRO is a thyroid-specific quality of life (QoL) questionnaire applicable to patients with benign thyroid disorders. There is substantial evidence for its clinical validity and reliability in patients with benign thyroid disorders. Our aim was to develop a validated Polish version of this questionnaire (ThyPROpl). MATERIAL AND METHODS ThyPROpl was translated and validated according to standard methodology for translation of patient-reported outcomes (PRO). Firstly, two independent translations from English to Polish were performed by two translators native in Polish, and a consensus version was reached in collaboration with an in-country consultant. A third translator prepared a back-translation from Polish to English, which likewise was reviewed by the in-country consultant. The backwards translation was reviewed by a PRO translation expert native in English (Health Research Associates HRA) and by the developer of ThyPRO, who provided additional revisions. Finally, ThyPROpl was tested among five patients with thyroid disorders with cognitive interview techniques, and new changes and clarifications needed for its full understanding were made. RESULTS ThyPROpl is a linguistically validated version of the original ThyPRO questionnaire. CONCLUSIONS We recommend ThyPROpl for the evaluation of QoL among Polish patients with benign thyroid disorders. ThyPRO has now been translated into 13 languages.