"Further, the selection criteria for randomized trials may limit generalizability to the population." Clinical trials suffer from extreme selection bias
Department of Health and Human Services, Centers for Disease Control and Prevention, National Center for Chronic Disease Prevention and Health Promotion, Office on Smoking and Health, 2014
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As in the phone sample, in adjusted analyses, older adults (OR = 1.73, 95% CI = 1.24, 2.42), females (OR = 1.37, 95% CI = 1.08, 1.72), and smokers of light cigarettes (OR = 2.25, 95% CI = 1.78, 2.84) were more likely to report past brand switching (Table 3)
The agency conducts assessments or evaluations to determine whether communities have been exposed to hazardous waste, and provides health information to prevent harmful exposures and related adverse effects to public health
Paradise has the youngest population in Newfoundland and Labrador