Farah is surveying people by phone from many different areas throughout the United States. She records their zip codes in order to keep track of what areas the participants are from.

categorical, operational, self-report

Explanation:

the categorical variable is A comparison of self-report and interview measures in the survey

the operational varailble is the survey validation of a self-report measure of individuals lastly the feasibility of self-report pain intensity measures in carrying out the survey.

a is the final ! : )

answer; generalizability;