【Objective】 To add superior items into the “Social Relationships” domain of WHOQOL-BREF by item response theory (IRT). 【Methods】 Nominal group worked interactively with focus group to build the item pool. Superior items were selected using IRT

traditional methods and experts’ importance rating to add into the “Social Relationships” domain. We administered the scale to 700 parents by quota sampling

and estimate the discrimination α

difficulty b1-b4

Item Information Function and Differential Item Functioning (DIF) of items. We also analyzed the property of items according to the dispersion degree

correlation coefficient

factor analysis

Cronbach’s α coefficient

multiple linear regression and experts’ importance rating. 【Results】 Three items D36

F14.3

A1 were selected to be added into “Social Relationships” domain according to the above methods. 【Conclusion】 The revised scale WHOQOL-BREF-R was developed on the strict procedures according to IRT.