Table 2 Incidence of amyotrophic lateral sclerosis (45–74 year age group) in selected studies with prospective cohort design, age adjusted to the 1990 US population
CountryYearsPopulationIR95% CI IRM:F ratio
Scotland19885 035 3155.24.1–6.41.8
Ireland*1995–973 626 0876.05.1–6.91.3
Washington (US)1990–952 589 1645.54.7–6.41.1
Piemonte (Northern Italy)*1995–964 418 5035.44.6–6.31.3
Puglia (Southern Italy)*1998–994 086 6134.22.6–5.71.6

  • *Used the El Escorial diagnostic criteria for inclusion of cases.

  • IR, incidence rate.