Development and validation of the health-related quality of life instrument for Chinese infertile couples: a mixed-methods study protocol

Background Infertility and its treatment have negative impacts on a couple's marital relationship, sexual life, psychological state and interpersonal relationships, causing personal distress. Health-related quality of life (HRQoL) has become an important component of health outcomes. HRQoL instruments developed in western culture are not always appropriate for use in China due to cultural differences. Probably due to the unique concept of fertility in China, infertility patients can be looked down upon and the family may feel shameful. This study aims to develop a HRQoL instrument for infertile couples based on the Chinese social and cultural setting. Methods Complementary mixed methods will be used to develop a new HRQoL instrument for Chinese infertile couples. The study consists of four stages: the first stage will involve a systematic review and qualitative interviews to construct draft candidate items. In the second stage, quantitative research [e.g., exploratory factor analysis (EFA), item response theory (IRT)] and cognitive interviews will be used for item selection. The third stage will be instrument validation, in which classical test theory (CTT) and IRT will be applied. In the final stage, the minimal clinically important difference (MCID) will be calculated by using distribution-based methods and anchor-based methods (e.g., logistic regression, receiver operating characteristic curve). Discussion The new HRQoL instrument for Chinese infertile couples will be developed, which will provide a standard and effective HRQoL instrument in clinical outcome assessment and health outcome measurement.