Table 3.

Hazard ratios (HR) from the Weibull and exponential regression models for all-cause mortality to 31^st December 2007 using reference relative time as the time-scale

	Relative time as time-scale				Relative time as time-scale
	Weibull model*				Exponential model**
	HR	95 % CI		P value	HR	95 % CI		P value
Never smoked	1.00				1.00
Light smoking	1.21	1.00	1.46	0.051	1.20	0.99	1.45	0.058
Medium smoking	1.68	1.38	2.05	<0.001	1.63	1.34	1.99	<0.001
Heavy smoking	2.01	1.51	2.68	<0.001	1.96	1.47	2.61	<0.001
Former smoking	0.89	0.66	1.21	0.465	0.90	0.66	1.22	0.485
Male	1.00				1.00
Female	1.10	0.92	1.32	0.304	1.08	0.90	1.30	0.383
RRR light smoking	1.35	1.07	1.70	0.012	1.33	1.05	1.68	0.016
RRR medium smoking	1.13	0.87	1.46	0.361	1.13	0.87	1.46	0.351
RRR heavy smoking	0.98	0.61	1.58	0.942	0.98	0.61	1.58	0.943
RRR former smoking	1.11	0.68	1.80	0.681	1.10	0.68	1.78	0.702
Byssinosis absent	1.00
Byssinosis present	1.04	0.93	1.16	0.484	1.04	0.93	1.16	0.524
Cough and phlegm absent	1.00
Cough and phlegm present	1.07	0.97	1.18	0.158	1.08	0.98	1.19	0.142
One decade in the cotton industry	0.91	0.88	0.94	<0.001	0.92	0.89	0.96	<0.001
FEV1: 10 % decrease below normal	1.07	1.04	1.10	<0.001	1.07	1.04	1.10	<0.001
FEV1 to FVC ratio: decrease of 10 %	1.01	0.95	1.07	0.763	1.02	0.96	1.0800	0.571

* LogL = −1813.7, shape 1.08 (95 % CI 1.04–1.12)

** LogL = −1822.9