In the July issue of Archives of Neurology, researchers reported studying the smoking habits of 12000 people (3000 with Parkinson's disease and 9000 healthy people). They found that those who had smoked the most (the equivalent of a pack a day for 60 years) had the lowest risk of getting Parkinson's disease.Was this anecdotal evidence, an observational study or an experiment?
(Im leaning towards observational study but I don't know)
Based on the description you provided, this study can be categorized as an observational study. An observational study involves observing and analyzing subjects without any intervention or manipulation by the researchers. In this case, the researchers observed and collected data on the smoking habits of 12,000 individuals, including both those with Parkinson's disease and healthy individuals, without any intervention or manipulation. They then analyzed the data to identify any potential relationships between smoking habits and the risk of developing Parkinson's disease.
