Table 5.

Period of diagnosis HRs and 95% CIs for death

		Univariate HR (95% CI)	Multivariate HR (95% CI)
	Deaths/Cases		Basea	Base + Surgeryb	Base + Surgery + Radiotherapyc	Base + Surgery + Radiotherapy + First Course Non-TMZ Chemod	Base + Surgery + Radiotherapy + First Course Non-TMZ Chemo + First Course TMZ Chemoe
Full cohort: 1618 deaths/1645 cases
Period of diagnosis
1997–2000	516/518	1.00 (reference)	1.00 (reference)	1.00 (reference)	1.00 (reference)	1.00 (reference)	1.00 (reference)
2001–2004	582/586	0.96 (0.85–1.08)	0.91 (0.80–1.02)	0.91 (0.81–1.03)	0.92 (0.81–1.04)	0.91 (0.80–1.03)	1.06 (0.93–1.21)
2005–2008	520/541	0.82 (0.73–0.93)	0.72 (0.64–0.82)	0.70 (0.62–0.80)	0.74 (0.65–0.84)	0.73 (0.64–0.83)	1.01 (0.86–1.19)
Period effect P		.0040	<.0001	<.0001	<.0001	<.0001	.60
Trend P		.0015	<.0001	<.0001	<.0001	<.0001	.84
Restricted cohort (treated with resection and radiotherapy): 910 deaths/932 cases
Period of diagnosis
1997–2000	303/305	1.00 (reference)	1.00 (reference)	1.00 (reference)	1.00 (reference)	1.00 (reference)	1.00 (reference)
2001–2004	324/327	0.87 (0.75–1.02)	0.81 (0.69–0.95)	0.81 (0.69–0.95)	0.81 (0.69–0.96)	0.80 (0.68–0.94)	1.05 (0.87–1.25)
2005–2008	283/300	0.71 (0.60–0.83)	0.60 (0.51–0.71)	0.61 (0.52–0.73)	0.62 (0.52–0.73)	0.60 (0.51–0.72)	1.02 (0.79–1.31)
Period effect P		.0002	<.0001	<.0001	<.0001	<.0001	.86
Trend P		<.0001	<.0001	<.0001	<.0001	<.0001	.86

Abbreviations: Chemo, chemotherapy; CI, confidence interval; HR, hazard rate ratio; TMZ, temozolomide.

^aAdjusted for age at diagnosis (≤39 y, 40–44, 45–49, … 80–84, 85+) and baseline Charlson comorbidity score (0, ≥1, unknown).

^bAdditionally adjusted for surgery (biopsy only, partial resection, gross total resection, resection not otherwise specified), modeled as a time-updated covariate.

^cAdditionally adjusted for radiotherapy (no, yes, unknown), modeled as a time-updated covariate.

^dAdditionally adjusted for first course non-TMZ chemotherapy (no, yes, unknown), modeled as a time-updated covariate.

^eAdditionally adjusted for first course TMZ chemotherapy (no, yes, unknown), modeled as a time-updated covariate.