Table 1.

Hosmer-Lemeshow goodness of fit test for POSSUM for 30-day mortality

Deciles of risk (%)	Number of patients	Number of observed deaths	Number of expected deaths	Mean risk of predicted mortality	O:E (95% CI)	X 2HL statistic
0-10	1501	15	71.96	0.05	0.21 (0.12 – 0.36)	47.36
10-20	514	19	72.88	0.14	0.26 (0.16 – 0.43)	46.42
20-30	216	16	52.36	0.24	0.31 (0.17 – 0.53)	33.33
30-40	133	9	45.64	0.34	0.20 (0.10 – 0.40)	44.78
40-50	66	6	29.38	0.45	0.20 (0.09 – 0.49)	33.54
50-60	51	8	27.61	0.54	0.29 (0.14 – 0.64)	30.37
60-70	34	5	21.84	0.64	0.23 (0.09 – 0.61)	36.29
70-80	22	7	16.40	0.75	0.43 (0.18 – 1.04)	21.26
80-90	12	2	10.00	0.83	0.20 (0.05 – 0.81)	38.40
90-100	3	1	2.87	0.96	0.35 (0.07 – 3.82)	27.08
0-100	2552	88	350.94		0.25 (0.20 – 0.32)	358.73

X²HL statistic =358.73; df =8; p <0.0001.