Table 1.

Means, Standard Deviations, and Reliability Estimates for PROMIS Global Health Scales

	Mean	SD	Lower Quartile	Upper Quartile	Quartile Range	Alpha	Marginal Reliability
GPH-4	49.10	9.21	42.84	54.54	11.70	0.81	0.79
GPH-2	49.21	8.71	44.32	56.03	11.71	0.73	0.70
Global01	49.41	7.56	46.77	54.26	7.49	NA	0.55
GMH-4	49.85	9.56	43.32	56.68	13.36	0.86	0.86
GMH-2	49.91	9.18	44.12	56.41	12.29	0.81	0.80

GPH-4 4-item global physical health scale, GPH-2 2-item global physical health scale, Global01 Single general health rating item, GMH-4 4-item global mental health scale, GMH-2 2-item global mental health scale, SD Standard deviation, Alpha Coefficient alpha, NA Not applicable, Marginal reliability is one minus the ratio of the average of the squared standard errors of observed expected a-posteriori (EAP) scores over the observed EAP score variance