Table 3.

The Completeness and Positive Predictive Value

Registry	DCCG n = 366		Total	Completeness	PPV
	+	–
DNPR and/or DNPatR	153	102	255	42 (37–47)	60 (54–66)
DNPR	118	89	207	32 (27–37)	57 (50–64)
DNPatR	71	22	93	19 (15–23)	76 (68–85)

Notes: The completeness: number of patients registered in the both the Danish Colorectal Cancer Group (DCCG) and each registry (the Danish National Patient Registry (DNPR) and the Danish National Pathology Registry (DNPatR)) (numerator), divided by the number (n=366) registered in the DCCG (denominator). The positive predictive value (PPV) was calculated as the number of patients with a registered diagnosis in both the DCCG and each registry, divided by the total number of patients registered with a diagnosis of peritoneal metastases in the respective registry.