"So if you have hoarseness with tobacco or alcohol use, that would be a significant risk factor for cancer or other problems of the throat that could be serious.
VOA: special.2009.09.02
It said that a study of US and Japanese youth had suggested playing violent video games was "a significantriskfactor for later physically aggressive behaviour".
Not just because other factors such as breast-feeding confound it, but because research suggests it is not as significant a riskfactor as breast density.