. Author manuscript; available in PMC: 2018 May 1.

Published in final edited form as: Qual Life Res. 2016 Nov 4;26(5):1119–1128. doi: 10.1007/s11136-016-1450-z

Table 4.

Full-Sample Comparisons between Linked and Actual Scores

Scale	Linking Method	Correlation	Mean Difference	SD of Differences	RMSD
ASR	Equipercentile None	.79	0.30	6.35	6.35
	Equipercentile Less	.78	0.72	6.94	6.98
	Equipercentile More	.78	0.76	7.04	7.08
	IRT–Fixed Anchor Crosswalk	.80	0.64	6.29	6.32

BSI	Equipercentile None	.86	0.17	5.21	5.21
	Equipercentile Less	.86	0.11	5.23	5.23
	Equipercentile More	.85	0.35	5.46	5.47
	IRT–Fixed Anchor Crosswalk	.87	0.35	5.09	5.10

Abbreviations: ASR=Adult Self Report; BSI=Brief Symptom Inventory; IRT=Item Response Theory; RMSD=Root Mean Square Difference