Control Variables

Several known predictors of personal consumption as informed by the literature were used in the study. Past research has found age (Jones et al., 1992; McAlaney and McMahon, 2007), gender (McAlaney and McMahon, 2007; Rimal, 2008), year in college (Perkins, 2002), age of first drink (Real and Rimal, 2007), money available for drinking (Connolly et al., 1992; Darmody et al., 2005; Bellis et al., 2007), drinking group size (Cutler and Storm, 1975; Demers et al., 2002), communication about alcohol (Dorsey et al., 1999a; Jamison and Myers, 2008) and living arrangement (Jones et al., 1992) to be associated with personal consumption. Age was coded as a categorical variable in the pilot study (see appendix 4 for pilot questionnaire). 4 response options were provided namely, 18-21 years, 22-25 years, 26-29 years and 30 or above. However, the pilot analysis revealed that using a specific value of age where possible is more useful, realistic and practical for the analysis. Hence in the final questionnaire, it was included as an open ended numerical variable.

Gender was included as a dichotomous variable coded 1 for males and 0 for females.

Year in college was included as a 6 point variable coded 0 for ‘less than 1 year’ to 5 for ‘5 or more years’.

Age of first drink was included as a variable with 9 response options coded 0 for ‘never had a drink’, 11 for ‘11 years or younger’ through to 18 for ’18 and above’. Based on feedback from the pilot survey, an explanatory line ‘other than just a sip’ was included in the final questionnaire for clarification.

Money available for drinking in a typical week was an 8 point variable having response options ranging from‘€ 20 or less’ to ‘more than € 140’ with an increment of € 20 in each step. For simplification, the variable was coded by choosing the midpoint for each category. Based on the feedback from the cognitive interviews, an explanatory line was included in brackets to facilitate the choice of an appropriate response option. The final question was phrased as How much money is available to you in a typical week for drinking? (Related costs such as food and taxis included)?

Drinking group size was included as a variable with 5 response options in the pilot questionnaire namely ‘Alone’, ‘1’, ‘2-3’, ‘4-9’ and ’10 or above’ based on Demers and others (2002). Further, it was contextualized into two questions querying one’s drinking group size on a ‘weekend night’ and when the respondent had ‘college the following day’. However, it was also felt that contextualizing the measure caused confusion to the students and did not add any usefulness to the analysis. Also, based on student feedback, narrower response options were provided in the final questionnaire. Thus, the final measure comprised a single question phrased as ‘How many people do you usually drink with on a typical occasion?

The composition of drinking group was measured with a single matrix type question which required participants to select all peer groups they usually drank with. The possible options to choose from included one’s boyfriend/girlfriend, class mates, flat mates, friends from college,

friends from outside college, work mates, neighbours, siblings, parents and other relatives. This question helped in formalizing the strategy for wave 2 of the study, as described in section 5.6.

Living arrangement was a categorical variable with 3 response options; ‘I am living with parents’, ‘I am living in a shared accommodation’ and ‘I am living independently and alone’. A fourth option was added in the final questionnaire namely ‘I am living with partner and/or dependent others’.

The pilot questionnaire examined Frequency of communication about alcohol by first asking a general question about how often one communicated with the different people they drank with.

How frequently do you communicate with the people you typically drink with? Please select the appropriate answer for all categories that apply to you.

Less than once a month Once a month Twice a month Once a week Twice a week 3-4 times a week 5-6 times a week Everyday Boy Friend / Girl Friend Class Mates Flat Mates Friends from college Friends from outside college Work Mates Neighbours Siblings Parents Other relatives

This was followed by a series of questions inquiring how often one had talked with the chosen people about specific drink related topics in the past month. 6 topics were included based on Dorsey and colleagues (1999a) namely, safer sex practices, effects of drinking too much alcohol, unwanted sexual advances caused by drinking, binge drinking, physical violence, injuries or fights and feeling sick as a result of drinking. This was a matrix type question which is reproduced next.

Think about the past month. Approximately how many times have you spoken with the people you typically drink with about ‘The Effects of Drinking too much Alcohol’?

Please select appropriate answers for all categories that apply to you.

Never _times 1-2 _times 3-4 _times 5-6 _times 7-8 _times 9-10 11 or more _times Boy Friend / Girl Friend Class Mates Flat Mates Friends from College Friends from outside college Work Mates Neighbours Siblings Parents Other relatives

The question was repeated for all 6 topics.

Respondent feedback indicated that the measure caused confusion, required students to do a lot of thinking and often returned partially completed and doubtful responses as students perceived their selves to be reflected negatively if they reported discussing certain topics.

Based on this feedback, the final questionnaire included two questions which are reproduced below

2. How often in a typical week do alcohol/drinking come up in your conversations with others?

Such items on peer communication have been administered in prior studies such as Real and Rimal (2007). These questions were accompanied by an explanatory note highlighting that the question meant casual day to day conversations.