1. Pulmonary cases, culture and smear status
Proportion ss+ or c+

2. Pulmonary cases, culture (by citizenship) and smear status
Proportion ss+ or c+

4. The Netherlands, pooled data 1996-2002
(N=6,749 pulmonary cases)
Objective - Comparing proportions of sputum smear positive cases between urban and non-urban settings, adjusting for citizenship.

5. 1) Nationals RR=1.27 (95%CL 1.15-1.41), P<10-5 SMEAR Total + - CITY
SMEAR
Total + -
CITY
336
(40.6%)
491
827
691
(31.9%)
1,472
2,163
1,027
1,963
2,990
RR=1.27 (95%CL ), P<10-5

6. 2) Non-citizens SMEAR Total + - CITY 591 (43.1%) 780 1,371 797 (33.4%)
SMEAR
Total + -
CITY
591
(43.1%)
780
1,371
797
(33.4%)
1591
2,388
1,388
2,371
3,759
RR=1.29 (95%CL ), P<10-6
Crude RR = 1.29
Summary RR=1.28
Therefore the adjustment does not explain the difference (ie no confounding by citizenship for the association between smear positivity and dwelling in cities).