Table 5.: Covariance analysis of post-test hospital depression scores in control and intervention groups with pre-test control.

Source	Dependent variable	SS	df	MS	F	Sig.
Pre-test hospital depression	Immediately after surgery	33.69	1	33.69	37.74	0.000
	Two months after surgery	69.61	1	69.61	0.31	0.58
	Four months after surgery	2.62	1	2.62	1.42	0.237
Intervention group	Immediately after surgery	145.76	1	145.76	163.27	0.000
	Two months after surgery	56.13	1	56.13	0.25	0.619
	Four months after surgery	38.07	1	38.07	20.58	0.000
Error	Immediately after surgery	6339	71	0.893
	Two months after surgery	1595828	71	224.76
	Four months after surgery	13132	71	1.85
Total	Immediately after surgery	8585	74
	Two months after surgery	28946	74
	Four months after surgery	8308	74