Sampling and Related Issues

5.6.1.1 Campus Structure at DIT

The Dublin Institute of Technology (DIT) was established officially in 1993. It was constituted from six higher education colleges of the City of Dublin Vocational Education Committee (CDVEC) (Duff et al., 2000). These colleges, located in the city centre both south and north of the River Liffey, had provided applied and higher vocational education in the areas of technology and business for over a century and in their new form came to be known as DIT. While plans are underway for the consolidation of DIT to a new premises located at Grangegorman, to date the institute comprises 6 separate campuses it originated from. The following map shows the location of these campuses around the Dublin City encircled and marked in red.

Figure 4: Location of DIT Campuses around Dublin City

The following table describes the distribution of various academic disciplines across these campuses

Aungier Street Campus College of Business

Kevin Street Campus College of Sciences and Health

Bolton Street Campus College of Engineering and Built Environment

Cathal Brugha Campus College of Arts and Tourism

College of Sciences and Health

Mountjoy Square Campus

School of Art and Design

School of Social Sciences and Legal Studies

Rathmines Campus College of Arts and Tourism

5.6.1.2 Recruitment of Subjects

Participants for the second stage of this study were recruited from the Aungier Street campus, which is one of the largest campuses of DIT. The choice of campus was aided by a preliminary analysis of the data from stage 1. Three key results provided impetus for selecting Aungier Street campus. One, 32% of the sample from stage 1 came from the Aungier Street campus making the response rate from this campus the highest among all. Two, descriptive analysis suggested that the gender distribution among the respondents from this campus (as extracted from the main sample) was quite balanced (48% male Vs 52% female) as opposed to other campuses. The Bolton Street and the Kevin Street for example are primarily male campuses with the analysis reporting 87% and 70% males respectively whereas the Cathal Brugha Street and the Mountjoy Square campuses are predominantly female with the survey reporting 71% and 75% females respectively. These results were generally consistent with the records of the registrations office at DIT. The Rathmines Road campus only comprised 1.6% of the sample and was therefore not considered for stage 2. Last, the actual drinking norm at the Aungier Street campus as deduced from the self reports of respective respondents was consistent with the actual drinking norm of the main sample for all three dimensions of alcohol use. The following table shows the mean values for all campuses.

Frequency of drinking (days in a typical month)

No. of drinks (typical occasion)

Frequency of drunkenness (days in a typical month)

Main Sample 4.91 8.68 3.26 Aungier St 5.06 8.65 3.44 Bolton St 5.12 10.21 3.47 Kevin St 4.51 8.49 2.76 Cathal Brugha 5.01 7.74 3.29 Mountjoy 4.66 7.24 3.24

Table 2: Mean alcohol consumption across DIT and individual campuses

Based on these findings, it was inferred that the attributes specifically gender and drinking rates of the respondents from this campus best depicted the main sample.

Next, 545 potential people from Aungier Street campus were categorized into three cohorts according to their drinking intensity. This categorization was based on Beck and Treiman (1996) which provides a criteria of low, moderate and heavy drinking individuals. The following table presents the categorization schema as laid out in the original study.

Frequency of drinking No. of drinks (per occasion) Frequency of Drunkenness Low intensity drinkers Once a month or less 2 drinks or less Never get drunk

Moderate intensity drinkers

Exceeded low intensity drinkers on one or more of these items but did not meet the criteria for high intensity drinkers High intensity drinkers Once a week or more 5 or more drinks Once a month or

more Table 3: Drinking Intensity Criteria (Beck and Treiman, 1996)

Two modifications were made to ensure consistency with the response options provided in the web survey and appropriateness within an Irish context. The frequency of drunkenness for low intensity drinkers was classified as ‘once a month or less frequently’ as opposed to ‘never’ and that for high intensity drinkers as ‘once a week or more frequently’ as opposed to ‘once a month or more’ in the original study. These amendments were considered necessary because the original study was carried out in the US where the criterion for low, heavy and moderate drinking might not necessarily be the same as in Ireland which is known to be quite tolerant of alcohol use and drunkenness. These modifications were made in the light of Delaney and Harmon et al (2007), a mixed methods study conducted by University College Dublin on the perceptions of excessive drinking by Irish college students.

Frequency of drinking No. of drinks (per occasion) Frequency of Drunkenness Low intensity drinkers Once a month or

less frequently 2 drinks or less

Once a month or less frequently Moderate intensity

drinkers

Exceeded low intensity drinkers on one or more of these items but did not meet the criteria for high intensity drinkers High intensity drinkers Once a week or

more 5 or more drinks

Once a week or more Table 4: Drinking Intensity Criteria for the Current Study

Further, those who met the criteria on any one item for high intensity were also classified as high intensity drinkers e.g. someone who drinks 2-3 days a month, consumes 9 drinks on an occasion but believes that he/she never drinks to get drunk was also classified as a heavy drinker.

5.6.1.3 Sample Size

6 email lists of potential participants were prepared based on random sampling. The invitations to take part in the interview were sent out to one list at a time followed by a reminder email a week later. A total of 26 interviews were conducted between 28th _{January and 17}th _{Feb, 2011.}

The cessation of interviews occurred in response to theoretical saturation. Specifically, after the 20th interview, there was saturation in the topics where additional interviews were producing the same themes and material regarding drinking norms and their development and sustainment in students' networks. A related point is that the goal of these interviews was not to reach statistical representativeness but to understand the functional aspects of the ego networks and examine how the composition and structure of networks contributed to the formation and dissemination of drinking norms within them.

Small samples like this are typical of qualitative studies, where the goal is not to reach statistical representativeness but to explore theoretical aspects of a social phenomenon (Curry et al., 2009). For example, Bellotti (2008) is a qualitative ego network study of a non representative sample of 23 single youth in Italy. Carpentier (2007) and Grosser (2010) are other examples of qualitative network studies with non representative small samples of n = 49 and n = 30 respectively.