. 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 2.

Classical Reliability Information

Scale(s)	Number of Items	Cronbach’s Alpha	Corrected Item-Total Correlation
Scale(s)	Number of Items	Cronbach’s Alpha	Minimum	Average	Maximum
ASR	14	.89	.35	.58	.75
BSI	6	.91	.61	.76	.85
PROMIS	8	.96	.81	.85	.90
ASR+PROMIS	22	.95	.34	.67	.86
BSI+PROMIS	14	.97	.61	.81	.89
ASR+BSI+PROMIS	28	.97	.34	.69	.87

Note: All correlations are significant at the p < .01 level. No scale would have had a higher alpha if an item were dropped.

Abbreviations: ASR=Adult Self Report; BSI=Brief Symptom Inventory; PROMIS=Patient Reported Outcomes Measurement Information System