Looks like all the highlighted questions are of the form "Has a <i>doctor or healthcare provider</i> told you X?" and "Has a <i>doctor or healthcare provider</i> diagnosed you with Y?" They seem to be controlling for the usual Education, Age, Gender, Income, and Race. Are they controlling for who tends to use / trust the medical establishment? There are religious sects who discourage going to the doctor, groups who deny the existence of mental illnesses like ADHD and depression, and growing general distrust of the medical establishment (all heavily weighted on one side of the political spectrum).