Final answer:
To establish causality between smoking and lung cancer, it is necessary to find correlation, conduct experimental studies, perform statistical analysis of multiple studies, and consider expert opinions. Smoking is linked to numerous cancers due to the presence of carcinogens in tobacco smoke, supporting the causal relationship.
Step-by-step explanation:
To establish causality for the claim that smoking causes lung cancer, several factors are necessary. Firstly, a correlation between smoking and lung cancer needs to be observed. This shows a statistical association between the two variables. Secondly, experimental studies are crucial as they provide evidence of a direct link by controlling for other variables and demonstrating that smoking indeed leads to lung cancer. Thirdly, comprehensive statistical analysis of data from multiple research studies can strengthen the causal argument by pooling results and showing consistency across different populations and settings. Fourthly, while not necessary for establishing causality, expert opinions on the relationship between smoking and lung cancer offer interpretations of the data and conclusions drawn from years of research by those specialized in this field.
Tobacco smoke contains 50 known carcinogens, and smoking is responsible for 90 percent of lung cancers. Beyond lung cancer, tobacco use increases the risk of several other cancers, reinforcing the causal link between smoking and cancer. Additionally, factors such as exposure to radon gas, asbestos, and secondhand smoke, as well as hereditary risk, can compound the risks associated with smoking.