Chapter 3, Appendix Figure 1:
Asthma admission rates for European countries, age 5-9 v 10-14 years.

Rank correlation: r = 0.97, p<0.001

Source: WHO Hospital Morbidity Database, accessed November 2013.

Admissions per 100,000 per year, age 10-14
Admissions per 100,000 per year, age 5-9