A recent epidemiological study found that businesspeople who travel internationally on business are much more likely to suffer from chronic insomnia than are businesspeople who do not travel on business.
Evidence
A recent epidemiological study found that businesspeople who travel internationally on business are much more likely to suffer from chronic insomnia than are businesspeople who do not travel on business.
International travelers experience the stresses of dramatic changes in climate, frequent disruption of daily routines, and immersion in cultures other than their own, stresses not commonly felt by those who do not travel.
Conclusion (thus)
It is likely that these stresses cause the insomnia.
Evaluate
The argument mistakes correlation for causation. That international business travel and insomnia are correlated does not establish that the stresses of international travel cause insomnia. Perhaps something else can explain why international business travelers are more likely to suffer from chronic insomnia than those who do not travel on business.