The section “Study design and participants“ is rather questionable based on dependence upon the BRFSS survey. Most of their citations about this survey attempt

The section “Study design and participants“ is rather questionable based on dependence upon the BRFSS survey. Most of their citations about this survey attempt to adjust for and explain how they have accounted for the fact that a random telephone survey is extremely unreliable in this age, and several of their citations do not even link to anything functional.