Table 4.

Calculation of the preoperative risk score and correlation to the occurrence of postoperative pancreatic fistula

Factor				Value
Age >66 years				+1
Preoperative diagnosis other than pancreatic carcinoma or chronic pancreatitis				+1
History of smoking				−1
History of weight loss				−1
History of acute pancreatitis				−1
Sum score				High risk: sum of 1 or 2
				Medium risk: sum of −1 or 0
				Low risk: sum of −3 or −2

POPF grade	Training dataset			Validation dataset
	Preoperative risk score			Preoperative risk score
	Low	Medium	High	Low	Medium	High
None	14	22	7	43	117	15
	100.0%	73.3%	38.9%	78.2%	70.1%	26.3%
A	0	5	7	8	27	20
	0.0%	16.7%	38.9%	14.5%	16.2%	35.1%
B	0	1	2	1	11	6
	0.0%	3.3%	11.1%	1.8%	6.6%	10.5%
C	0	2	2	3	12	16
	0.0%	6.7%	11.1%	5.5%	7.2%	28.1%
	Correlation coefficient = 0.47			Correlation coefficient = 0.35
	P < 0.001a			P < 0.001a

The score was developed in the ‘training’ dataset of 62 patients and validated in an independent dataset of 279 patients

Numbers given are absolute and percentages refer to the total number of patients in one column

^aCorrelation coefficient and P-value for two-tailed Spearman's rank correlation

POPF, postoperative pancreatic fistula, Grades A–C according to International Study Group for Pancreatic Surgery definitions