Key points are not available for this paper at this time.
Adding a single item to a large cross-sectional population survey can cost as much as 100, 000. The 2-item variants of the PROMIS global health scales reduce the cost of use on national surveys by 50%, a substantial cost savings. These briefer scales are also more practical for use in clinical practice. The 2-item versions of the PROMIS global health scales display adequate reliability for group comparisons and their associations with other indicators of health are similar to that of the original 4-item scales. The briefer scales are psychometrically sound and reduce burden of survey administration.
Hays et al. (2017) studied this question.