Table 1. Variables used in analyses, their definitions, and categories or range
VariableDefinition or categories
Increasing or higher-risk drinkerScore ≥5 on AUDIT-C, same cut-off for all5,6,32
Past-year smokerIf stated:‘I smoke cigarettes (including hand-rolled) every day.’ ‘I smoke cigarettes (including hand-rolled), but not every day.’ ‘I do not smoke cigarettes at all, but I do smoke tobacco of some kind (eg, pipe, cigar, or shisha).’ ‘I have stopped smoking completely in the last year.
Receipt of alcohol brief interventionQuestion:‘In the last 12 months, has a doctor or other health worker within your GP surgery discussed your drinking?’If answered:‘Yes, a doctor or other health worker within my GP surgery offered advice about cutting down on my drinking.’ ‘Yes, a doctor or other health worker within my GP surgery offered help or support within the surgery to help me cut down.’ ‘Yes, a doctor or other health worker within my GP surgery referred me to an alcohol service or advised me to seek specialist help.’
Receipt of smoking brief interventionQuestion:‘Has your GP spoken to you about smoking in the past year (ie, last 12 months)?’If answered:‘Yes, he or she suggested that I go to a specialist stop smoking adviser or group.’ ‘Yes, he or she suggested that I see a nurse in the practice.’ ‘Yes, he or she offered me a prescription for Champix, Zyban, a nicotine patch, nicotine gum or another nicotine product.’ ‘Yes, he or she suggested that I use an e-cigarette.’ ‘Yes, he or she advised me to stop but did not offer anything.
GP visit in past year (increasing or higher-risk drinkers)See Receipt of alcohol brief intervention with additional answer option:’Yes, a doctor or other health worker within my GP surgery asked about my drinking.’And if replied ‘No’ and answered to follow-up question: ‘I have seen a doctor or health worker within my GP surgery in the last 12 months but did not discuss my drinking.’
GP visit in past year (past-year smokers)See Receipt of smoking brief intervention with additional answer options:‘Yes, he or she asked me about my smoking but did not advise me to stop smoking.’ ‘No, I have seen my GP in the last year but he or she has not spoken to me about smoking.’ ‘No, I have not seen my GP in the last year.’
GenderFemale, male, or non-binary (owing to the small proportion of participants who identified as non-binary, they were excluded from regression analyses)
Age, years16–24, 25–34, 35–44, 45–54, 55–64, or ≥65
Ethnic groupWhite or ethnic minority
NationEngland, Scotland, Wales; in sensitivity analysis, England divided into North (North East, North West, and Yorkshire and the Humber), Central (East Midlands, West Midlands, and East of England), and South (London, South East, and South West)
Social gradeMeasure of socioeconomic position using the National Readership Survey’s classification33 categories: ABC1 (high and intermediate managerial, administrative, or professional; and supervisory, clerical, and junior managerial, administrative, or professional) and C2DE (skilled manual workers; semi and unskilled manual workers; and state pensioners, casual or lowest grade workers, or unemployed with state benefits only); in sensitivity analysis: AB, C1, C2, D, and E
AUDIT-C scoreMeasure of risk of alcohol-related harm,5 range: 5–12
Strength of urge to smokeMeasure of tobacco dependence for past-year smokers,34 range: 0–5; if ‘Not at all’ [0] selected for Time with urge to smoke (‘How much of the time have you felt the urge to smoke in the past 24 hours?’, then question: ‘In general, how strong have the urges to smoke been?’; answer options: slight [1], moderate [2], strong [3], very strong [4], or extremely strong [5])
  • AUDIT-C = alcohol use disorders identification test consumption.