Table 2.

Validity evidence

Domain and items	Factor loading	Communality	Measurement error	Average variance extracted
F1 Technical level				0.66
n1	0.73	0.53	0.47
n2	0.80	0.64	0.36
n3	0.81	0.65	0.35
n4	0.90	0.81	0.19
F2 Coordination of support				0.71
n5	0.86	0.74	0.26
n6	0.83	0.68	0.32
F3 Structure and content				0.48
n7	0.76	0.58	0.42
n8	0.54	0.29	0.71
n9	0.73	0.54	0.46
n10	0.78	0.60	0.40
n11	0.76	0.58	0.42
n12	0.73	0.53	0.47
n13	0.71	0.51	0.49
n14	0.53	0.28	0.72
n15	0.65	0.42	0.58
F4 The role of the guideline				0.63
n16	0.70	0.49	0.51
n17	0.84	0.71	0.29
n18	0.82	0.67	0.33
n19	0.80	0.63	0.37