Figure 2 Scatterplots of the relationship between annual exposure to locally generated PM₁₀ at the home address expressed as μg/m³ and prevalence of cough without a cold surveys undertaken in (A) 1998 and (B) 2001 of a random stratified sample of 1–5 year old children in Leicestershire, UK. Each data point represents five centiles of unadjusted data sorted by exposure (n = 128 in 1998 and n = 115 in 2001).