The overall purpose of this study is to determine how accurately interviewers ask questions as well as how well respondents answer them through a process of behavior coding. The results of this study will identify problematic question wording and guide future interviewer training. Behavior coding, as a method, systematically describes interactions between interviewers and respondents through the application of a set of uniform codes that make reference to the behaviors that take place during an interaction. There are codes for the ideal question-and-response situation where the question is read as worded and the response easily fits into response categories. However, other codes exist to capture aspects of the interaction that are less than ideal. Deviations might indicate potentially problematic questions and reduced data quality. It should be noted that this is a qualitative study and therefore should not be misinterpreted as representative of the US population. This should be kept in mind when interpreting percentages in the summary of this report, in that they are also not representative of the population.