Completeness of the disease recording systems for dairy cows in Denmark, Finland, Norway and Sweden with special reference to clinical mastitis

Table 4 Country-specific completeness (95% confidence interval) of registration of farmer-recorded (FRD) clinical mastitis (CM) cases in four national databases, calculated as the proportion of FR CM cases found in a common disease database (CoDD) when allowing a date discrepancy of 7 days

Dataset		Denmark	Finland	Norway	Sweden
Original FRD	All cases	0.85 (0.80; 0.90)	0.45 (0.32; 0.58)	0.68 (0.57; 0.80)	0.61 (0.50; 0.72)
Original FRD	Veterinary-visited cases	0.90 (0.86; 0.94)	0.50 (0.41; 0.59)	0.77 (0.68; 0.86)	0.72 (0.63; 0.81)
Adjusted FRD^a	All cases	0.90 (0.87; 0.93)	0.51 (0.43; 0.59)	0.75 (0.67; 0.83)	0.67 (0.60; 0.75)
Adjusted FRD^a	Veterinary- visited cases	0.94 (0.92; 0.97)	0.56 (0.48; 0.64)	0.82 (0.75; 0.90)	0.78 (0.70; 0.85)
Adjusted FRD^b	All cases	0.80 (0.73; 0.87)	0.46 (0.37; 0.54)	0.67 (0.58; 0.77)	0.60 (0.51; 0.69)
Adjusted FRD^b	Veterinary- visited cases	0.90 (0.84; 0.95)	0.51 (0.42; 0.60)	0.76 (0.67; 0.86)	0.72 (0.63; 0.81)

The CoDD consisted of information retrieved from the four Nordic national cattle databases. The study was carried out during two 2-month periods in 2008.
^a Excess CoDD cases added to the FRD.
^b Only herds with good reporting to the FRD were included. The number of herds with good reporting was 48/105 (46%), 148/167 (89%), 142/179 (79%) and 105/129 (81%) in Denmark, Norway, Finland and Sweden, respectively.
CI = confidence interval. FRD = farmer-recorded data.

ISSN: 1746-6148