Table 2. Demonstration of group-based goodness-of-fit test for rheumatoid arthritis example.

			Goodness-of-fit test*
Group	FRS, %	N	o	e	SIR	z score	p-value
1	<2.58	88	2	0.84	2.38	1.22	0.22
2	2.59 – 4.79	88	5	2.14	2.34	1.89	0.058
3	4.80 – 8.20	87	4	3.81	1.05	0.10	0.92
4	8.21 – 13.59	88	10	6.63	1.51	1.30	0.19
5	13.60 – 21.96	87	23	10.28	2.24	3.86	<0.001
6	>21.96	87	40	21.93	1.82	3.80	<0.001
Total		525	84	45.63	1.84

o=observed number of events; e= expected number of events; SIR= standardized incidence ratio (o/e); KM=Kaplan-Meier estimate; FRS=Framingham risk score

^*Overall deviance=28.94, df=5, p<0.001