The Field Representative's Manual noted that an estimated number was acceptable. It provided further instructions to interviewers to convert responses given as the number of packs into the number of cigarettes, and for responses given as an average per week or month into the average per day.

In the 1970 survey, a respondent representing the family (a proxy) could answer the question associated with CIGSYRAGO for all other family members over age 17. As self-report is typically more accurate than proxy report, researchers may want to indicate this caveat when analyzing the data or interpreting results.