Codes and Frequencies
ALCDAYSYR reports the number of days per year during the past year that the sample adult drank alcoholic beverages.
Interviewers began the section of the survey on alcohol by stating, "These next questions are about drinking alcoholic beverages. Included are liquor such as whiskey or gin, beer, wine, wine coolers, and any other type of alcoholic beverage." They then asked, "In the past year, how often did you drink alcoholic beverages?" Respondents could frame an answer using various time units (e.g., "5 times a week," "once a month," "10 times a year"), and the interviewer recorded the number stated and the time period that fit the answer (i.e., "Never/None," "Week," "Month," or "Year"). For the original NHIS public use files, the National Center for Health Statistics recoded these data in terms of days per week (for ALCDAYSWK), in terms of days per month (for ALCDAYSMO), and in terms of days per year (for ALCDAYSYR).
The effect of reporting in time periods shorter than a year (i.e., times per week or per month) is evident in digit clustering in the frequencies for ALCDAYSYR. There is strong clustering of responses in codes that are multiples of 12, corresponding to responses given in terms of times per month. Users should, therefore, be wary of treating ALCDAYSYR as a simple interval variable.
The Field Representative's Manual for 1997-2001 forward directed interviewers to "always probe for an exact number. If the sample adult reports a range or interval, assist the sample adult in making an estimate by probing. For example, you might ask, 'Could you give me a more exact number?'" To the same end, beginning in 2000, the survey instrument instructed interviewers, "If necessary, prompt with 'How many days per week, per month, or per year did you drink?'"
- 1997-2013; 2014 2015 2016 2017 2018: Sample adults age 18+ who have had at least 12 drinks in any one year or at least 12 drinks in entire life
- 1997-2018 : SAMPWEIGHT