Considering data on a patient-reported outcome measure (PROM) for Chinese patients with thyroid diseases who speak Mandarin in China

The current study examined a newly-translated Simplified Chinese version of the Thyroid-Specific Patient-Reported Outcome Short Form (SC ThyPRO-39) among 179 thyroid patients in Mainland China. This study investigated whether the ceiling/floor effect (CFE) is present in responses to the SC ThyPRO-39. The appropriateness of regression modelling strategies for data with and without CFE were considered for a variety of predictor sets, and models were compared among six distributional models. With different predictor sets, the effect of gender and mode of administration (electronic interview versus self-administration) were of particular interest. Results suggested the use of Negative Binomial or Zero-inflated Negative Binomial as modelling strategies to fit the data with significant floor effect. There were also gender and mode effects on the scale scores. Findings indicated that overall, the SC ThyPRO-39 can be used as a patient-reported outcome measure among thyroid patients who speak Mandarin or read Simplified Chinese in China.