From: Detection and follow-up of chronic obstructive pulmonary disease (COPD) and risk factors in the Southern Cone of Latin America. the pulmonary risk in South America (PRISA) study
Proportion
Design Effect
1.0
1.5
2.0
2.5
3.0
0.26-0.50
30
45
60
75
90
0.25
32
48
64
80
96
0.20
40
100
120
0.15
53
107
133
160
0.10
200
240
0.05
320
400
480