Consider the aetiology of a disease from the combination of descriptive epidemiological data along with other information e.g genetics, microbiology, sociology etc
Why is it important to study epidemiology of diseases?
Because knowledge of epidemiology may help us to understand the impact of the disease, any aetiological factors, treatment needs, treatment effects, etc.
What was the 'natural history of periodontal disease in man' study?
It was a parallel cohort longitudinal study about male tea labourers in Sri Lanka with little/no access to oral care compared to 565 male students & teachers aged 17-31 in Oslo, Norway and the data was collected in 1969