Table 1.

City descriptive data on the study period, population, exposure (CO), outcome (daily number of deaths), and potential effect modifiers.

Location	Study period (month/year)	Population (×1,000)	Total no. of deaths	CVD	CO (mg/m3) [mean (10th–90th)]a	No. of CO monitors	PM (mean)	O3 (mean)	SMR	% of population> 75 years of age	Area
Athens	1/92–12/96	3,073	73	36	6.1 (3.5–9.2)	2	42.7	87.1	784	5.3	South
Barcelona	1/91–12/96	1,644	40	16	0.9 (0.4–1.7)	3	63.5	71.9	740	7.3	South
Basel	1/90–12/95	360	9	4	0.6 (0.4–1.1)	1	31.2	64.0	678	7.6	Northwest
Birmingham	1/92–12/96	2,300	61	28	1.0 (0.5–1.6)	1	24.5	55.7	895	6.5	Northwest
Budapest	1/92–12/95	1,931	80	40	5.1 (3.3–7.4)	8	41.0	83.8	1,136	6.6	Central-eastern
Geneva	1/90–12/95	317	6	2	1.5 (0.8–2.6)	4	39.7	67.3	608	6.4	Northwest
Helsinki	1/93–12/96	828	18	9	1.2 (0.7–1.9)	2	27.7	58.0	915	5.0	Northwest
Ljubljana	1/92–12/96	322	7	3	1.6 (0.6–3.0)	1	—	80.0	823	4.5	Central-eastern
London	1/92–12/96	6,905	169	71	1.4 (0.7–2.2)	3	28.8	44.9	851	6.5	Northwest
Lyon	1/93–12/97	416	9	3	3.8 (2.0–6.0)	4	41.8	66.6	579	8.5	Northwest
Milano	1/90–12/96	1,343	29	11	5.4 (2.9–8.7)	3	53.0	52.7	623	9.6	Northwest
Netherlands	1/90–9/95	15,400	342	143	0.6 (0.4–1.2)	5	40.1	69.8	757	5.5	Northwest
Prague	2/92–12/96	1,213	38	22	0.9 (0.5–1.5)	4	76.2	85.3	984	5.7	Central-eastern
Rome	1/92–12/96	2,775	56	23	4.1 (2.5–5.9)	5	58.7	47.5	585	6.2	South
Stockholm	1/90–12/96	1,126	30	15	0.8 (0.5–1.2)	2	15.6	65.0	666	11.0	Northwest
Teplice	1/90–12/97	625	18	8	0.7 (0.3–1.2)	5	47.9	55.5	1,173	3.5	Central-eastern
Torino	1/90–12/96	926	21	9	5.5 (2.8–9.1)	2	74.5	88.6	724	7.8	Northwest
Valencia	1/94–12/96	753	16	6	4.1 (2.4–5.9)	4	—	59.1	820	5.5	South
Zurich	1/90–12/95	540	13	6	1.2 (0.7–2.0)	3	31.3	66.8	666	7.2	Northwest

Abbreviations: —, no data; SMR, standardized mortality rate.

^aPercentiles.