Development of a disease-specific health-related quality of life questionnaire (THYCA-QoL) for thyroid cancer survivors

Abstract Background. To date, no valid instrument is available that focuses on specific health-related quality of life (HRQoL) issues that affect thyroid cancer survivors. The objective of this study was to develop and pretest a thyroid cancer specific HRQoL questionnaire that can be used in addition to the more general European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30). Material and methods. Potentially relevant issues were identified by a systematic literature review, a focus group meeting, and an issue list completed by six health care professionals (HCP) and 18 thyroid cancer survivors. Resultant issues were analyzed on importance and relevance (phase I). The issues were formulated into a long provisional list of questions (phase II). These questions were administered in combination with the EORTC QLQ-C30 to 306 Dutch thyroid cancer survivors to pretest the hypothesized scale structure (phase III). Although the development of this questionnaire was not set up as an international study, phases I-III are in agreement with the methodology of the EORTC guidelines. Results. The literature search, focus group and issue list completed by HCP and survivors resulted in 75 issues. These were reduced to create a 30 item provisional list. Pretesting led to a selection of 24 items with a good range of response. This resulted in the THYCA-QoL containing 24 items and seven conceptual scales. Conclusion. The THYCA-QoL in combination with the EORTC QLQ-C30 is ready for a large (international) scale validation study, and will assess HRQoL issues of most relevance and concern for thyroid cancer survivors.