significance level of 0.05, a confidence
level of 95%, with a power of 0.90 (90%)
and a coefficient of determination of 0.09
(median effect size) according to Cohen
16
.
A total of 228 young university students
were selected by stratified random
probability sampling with allocation
proportional to the size of the stratum.
The combinations were career (2: nursing
and industrial engineering) and grade (4:
1st, 2nd, 3rd and 4th year of studies), which
formed 8 strata. Within each stratum, one-
stage cluster sampling was used, where
the group of students formed each cluster.
2.2 Measuring instruments
To assess the sociodemographic
characteristics, a Personal Data
Questionnaire was used, which included
data such as age, sex, career, current
semester, as well as the prevalence of
alcohol consumption (ever in life, in the
last year, in the last month and in the last
week). To measure self-efficacy to resist
alcohol consumption, the Situational
Confidence Questionnaire
17
was used,
translated and adapted to Spanish by
Echeverría and Ayala
18
. This questionnaire
is made up of 39 items with a response
scale ranging from 1 to 6, where 1 denotes
“I could not resist the temptation to
consume alcohol for sure” and 6 denotes “I
could resist the temptation to consume
alcohol for sure”.)
The questionnaire includes the
intrapersonal and interpersonal subscales;
the intrapersonal subscale comprises
items 1 to 3, 7 to 13, 17 to 23, 27 to 33 and 36
to 39, which constitute the categories:
negative physical emotional states,
positive emotional state, impulses and
temptations, and personal control test.
The interpersonal subscale is made up of
items 4 to 6, 14 to 16, 24 to 26 and 34 to 35;
the minimum scale score is 39 and the
maximum is 234. This questionnaire has
shown Cronbach's Alpha consistency
between 0.94 and 0.97 and an explained
variance of 68.1% in various studies
conducted in Mexican high school
students
19,20
. In this study, an internal
consistency of 0.95 was obtained.
In order to evaluate self-control, the
Abbreviated Self-Control Scale
21
was used,
which was designed with the aim of
assessing self-control in university
students in the United States. This
instrument was adapted to Spanish in a
population of university students from
Argentina with an explained variance of
44% and internal consistency of the total
scale (α = .75)
22
. The scale consists of 13
items that are divided into two subscales:
self-discipline (items 6, 11, 5, 1, 7, 8, 2) and
impulse control (items 12, 13, 3, 9, 10, 4),
with five Likert-type response options
ranging from 1 (strongly disagree) to 5
(strongly agree) having a minimum score
of 13 and a maximum of 65. In the present
study, the Cronbach's Alpha coefficient
was 0.73.
Alcohol consumption was measured by
means of prevalence (once in a lifetime, in
the last year, in the last month and in the
last week), as well as the Alcohol Use
Disorders Identification Test (AUDIT) with
the aim of measuring drinking behavior
and problems related to alcohol
consumption in adults with problematic
alcohol consumption
23
. This questionnaire