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The College, Alcohol and Peers Study (CAPS)

Peer Groups and Broad Social Motives' Influence on College Student Drinking: A Multimethod Approach Using Alcohol Administration and Daily Diary

Status
Terminated
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT03890484
Enrollment
13
Registered
2019-03-26
Start date
2020-01-25
Completion date
2022-07-03
Last updated
2024-04-17

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Alcohol Drinking

Keywords

Alcohol use, Risk-taking, Anxiety, Motives, Multimethod

Brief summary

The present study will evaluate college students (N=100) from 2- and 4-year colleges/universities between 21-24 years old to assess anxiety, affect, broad social motives (BSM) and peer group influences on drinking and other risk-taking behaviors. This study will employ two sound scientific methods for testing behavior during drinking events (i.e., lab alcohol administration and daily diary) and use novel strategies to compare results of these two methods in the same sample. Using an ad-lib drinking paradigm, students' risk-taking, as measured by the Balloon Analogue Risk Task (BART), will be assessed when alone and during one of two randomly assigned peer group conditions (close friends or new peers). Participants will be allowed to freely drink (within safety limits) with their peer group prior to completing the BART again. These same students will complete daily electronic diaries on four weekends (Thursday - Sunday; total 24 assessments) regarding BSM, motives to drink, peers in their social group, alcohol use and consequences, and if/how their social group changed (e.g., few close friends to large party with many new peers) during the drinking event. Competing hypotheses will be tested such that: 1) anxiety is expected to be a stronger predictor of drinking behavior and greater differences in risk-taking in the new peer condition than close friend condition or 2) BSM is expected to be a stronger predictor of drinking behavior and greater differences in risk-taking in the close friend condition than new peers condition. Results are expected to be replicated in the daily diary reports. Further, this multimethod approach will allow us to evaluate how behavior assessed in the lab predicts naturally occurring behaviors in an uncontrolled setting. For example, the investigators will assess whether greater increases in self-reported risk-taking from baseline to after entering peer groups in the bar lab setting will predict heavier drinking on nights when most drinking companions are close friends reported during daily diary.

Detailed description

Participants (N=100) will be recruited through direct outreach to University of Washington (UW) students via the UW Registrar's directory list, as well as community flyers distributed at colleges in the local area, online advertisements, and word of mouth. Participants will complete screening measures online. Eligible participants will be stratified on sex, age, and past 30-day peak alcohol use and randomly assigned to one of two conditions: close friends (N=50), where participants will recruit two of their existing friends, or new peers (N=50), where participants will drink with two strangers. To ensure at least two eligible friends, those in the close friend group will be asked to provide email and phone numbers of five to seven close friends. Close friends will have to meet the same inclusion and exclusion criteria as target participants and will go through the same procedures as target participants during alcohol administration. For each pair of participants matched on the three strata (age, sex, alcohol use), strangers in the new peer group will be matched to the sex of the close friends of the other matched participant's group. Participants will be asked not to travel to the bar together to ensure they are not exposed to their peer group before entry to the bar, and must get to the lab without operating any vehicle with wheels (e.g. car, bike). Upon arriving to the lab, all participants and peers will review and sign the consent form, and provide a baseline breath alcohol content (BrAC) reading. Female participants and friends will also be asked to take a urine pregnancy test. Participants and friends will complete baseline measures and the Balloon Analogue Risk Task (BART) individually prior to entry to the bar. Then they will be taught the procedures for the daily diary portion of the study (see below). Participants will join their close friends or new peers in the bar and be given 20 minutes to relax while the researcher prepares the materials. After entering groups but prior to receiving alcohol, participants and peers will complete pre-alcohol measures and the BART. They will then be allowed to order anything from the bar menu for the following hour. Participants and close friends will be allowed to drink freely within limits (BrAC = .12%), for safety. During ad-lib, estimated BAC levels based on age, sex, and weight will be calculated prior to each drink served to ensure the safety of consuming each drink without interrupting social interaction and making the participant's BAC more salient by taking BrAC readings regularly. Participants or close friends whose BAC may exceed .12% will only be served placebo beverages for the remainder of the hour. BrAC readings will be taken at the end of ad-lib, every 10 minutes until peak BrAC is reached and readings are descending, and every 30 minutes thereafter. After ad-lib, participants will complete post-alcohol measures and the BART, then provided entertainment until they reach a BAC below .03%. The full protocol will take approximately 2.5 hours. On average, alcohol metabolizes at a rate of .015% per hour, so a participant who reaches .12% will be in the lab on average 8.5 hours. Once sober, participants and friends will be taken home in a taxi or ride share service (e.g. Uber, Lyft). Close friends will not complete the following daily diary protocols. Daily diary measures will start on the Thursday following each participant's alcohol administration appointment and be collected for potential drinking events on Thursday, Friday, and Saturday over the following four consecutive weeks. Each day, participants will be notified of surveys by text message at 4 pm and the following morning at 11am (Friday, Saturday, and Sunday) for a total of 24 assessments. Surveys will be available for 2 hours and reminders sent via text 30 minutes before closing. Afternoon assessments take approximately 5 minutes and measure BSM, motives to drink, motives to refrain from drinking, evening plans, and what type of peers they plan to spend the evening with (e.g. close friends, new peers, family, alone). For the daily diary, BSM items have been modified to select experiences which may vary daily (e.g. making social plans got me excited and energized today) and drinking motives have been modified into a brief prospective measure consistent with modifications used in other studies15. At morning assessments, participants will retrospectively report amount of drinks and other substances consumed, time spent drinking, and consequences experienced while drinking or currently (morning after drinking). Participants will be asked how many times their social group changed during the event defined as the majority of their drinking companions being of a different peer type than before. For instance, a participant may be at a house party with primarily close friends, but someone invites several people the participant does not know well and they are now drinking with mostly new peers. For each peer group reported (up to five groups), participants will report the following characteristics of the group: size (i.e. number of people they had direct contact with), number of drinking companions of each peer type (e.g. close friends, new peers, family), gender composition of the group (same-sex vs. mixed-sex), time spent with and drinks consumed with each group. On non-drinking evenings, participants will report similar information regarding their social groups and other activities. This survey will take approximately 5-7 minutes.

Interventions

BEHAVIORALPeer Type - New Peer

Participants drink with 2 unfamiliar confederate peers

BEHAVIORALPeer Type - Close Friends

Participants drink with 2 close friends

Sponsors

National Institute on Alcohol Abuse and Alcoholism (NIAAA)
CollaboratorNIH
University of Washington
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
BASIC_SCIENCE
Masking
NONE

Intervention model description

Participants will be randomly assigned to one of two conditions, which will run in parallel.

Eligibility

Sex/Gender
ALL
Age
21 Years to 24 Years
Healthy volunteers
Yes

Inclusion criteria

* currently enrolled in college * has consumed 3 or more alcoholic drinks in one sitting at least once in the past month * drinking frequency of once a week

Exclusion criteria

* past-month alcohol * past-month other substance dependence, * past-month mood disorder * past-month anxiety disorder * past-moth suicidal ideation * excessive alcohol use reaching a BAC greater than .30% in past month * history of serious medical conditions * regular use of prescription psychotropic or pain medication * history of negative reactions to alcohol * history of treatment for alcohol use disorder * pregnancy * nursing

Design outcomes

Primary

MeasureTime frameDescription
Alcohol UseDuring 1 hour ad-lib period, starting an average of 1 hour after Baseline.Number of drinks consumed
Alcohol Use - Daily Diary4 weeks following ad-lib.Number of drinks consumed, self-reported the morning after drinking events
Alcohol Consequences4 weeks following ad-lib.Self-report of the Young Adult Alcohol Problems Screening Test (YAAPST). Count of number of consequences experienced. Range: 0-27. Higher scores represent more consequences experienced.
Risk-takingChange from baseline (alone) to 20 minutes following Peer Type intervention.Scores on the Balloon Analogue Risk Task (BART). Scores are calculated by adding the number of pumps for unexploded balloons, with higher scores reflecting greater risk-taking. Range varies - explosions are at a random point between 1 and 128 pumps.

Countries

United States

Participant flow

Recruitment details

Participants were recruited through University registrar's list emails, flyers posted around campus, and social media advertisements. Participants were recruited and enrolled between December 2019 and July 2022. Recruitment was paused from March 2020 to August 2021 due to the COVID-19 pandemic and again from August 2022 until early termination in June 2023 due to key personnel and funding changes. Study effective termination was July 2022.

Pre-assignment details

Participants were completed informed consent and enrolled at the time of the alcohol administration session.

Participants by arm

ArmCount
New Peers
Participants will drink with two new peers (i.e. strangers), who they did not know prior to the study and their Peer Type. Peer Type - New Peer: Participants drink with 2 unfamiliar confederate peers
5
Close Friends
Participants will recruit and drink with two of their close friends and their Peer Type Peer Type - Close Friends: Participants drink with 2 close friends
8
Total13

Withdrawals & dropouts

PeriodReasonFG000FG001
Overall StudyLost to Follow-up11

Baseline characteristics

CharacteristicNew PeersClose FriendsTotal
Age, Categorical
<=18 years
0 Participants0 Participants0 Participants
Age, Categorical
>=65 years
0 Participants0 Participants0 Participants
Age, Categorical
Between 18 and 65 years
5 Participants8 Participants13 Participants
Age, Continuous21.4 years
STANDARD_DEVIATION 0.89
21.5 years
STANDARD_DEVIATION 0.76
21.46 years
STANDARD_DEVIATION 0.78
Broad Social Motives for Friends4.06 units on a scale
STANDARD_DEVIATION 0.44
4.58 units on a scale
STANDARD_DEVIATION 0.32
4.38 units on a scale
STANDARD_DEVIATION 0.44
Broad Social Motives for New Peers2.87 units on a scale
STANDARD_DEVIATION 0.23
3.94 units on a scale
STANDARD_DEVIATION 0.51
3.53 units on a scale
STANDARD_DEVIATION 0.68
Ethnicity (NIH/OMB)
Hispanic or Latino
0 Participants1 Participants1 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
5 Participants7 Participants12 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
0 Participants0 Participants0 Participants
Negative Affect1.4 units on a scale
STANDARD_DEVIATION 0.27
1.11 units on a scale
STANDARD_DEVIATION 0.14
1.22 units on a scale
STANDARD_DEVIATION 0.24
Positive Affect2.7 units on a scale
STANDARD_DEVIATION 0.68
3.16 units on a scale
STANDARD_DEVIATION 0.5
2.98 units on a scale
STANDARD_DEVIATION 0.6
Prior 30 day Alcohol Consequences16.2 units on a scale
STANDARD_DEVIATION 6.72
20 units on a scale
STANDARD_DEVIATION 15.76
18.54 units on a scale
STANDARD_DEVIATION 12.79
Prior 30 day Alcohol Use2.91 Number of standard drinks
STANDARD_DEVIATION 0.93
3.04 Number of standard drinks
STANDARD_DEVIATION 1.15
2.99 Number of standard drinks
STANDARD_DEVIATION 1.03
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Asian
1 Participants1 Participants2 Participants
Race (NIH/OMB)
Black or African American
0 Participants0 Participants0 Participants
Race (NIH/OMB)
More than one race
1 Participants0 Participants1 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Unknown or Not Reported
0 Participants0 Participants0 Participants
Race (NIH/OMB)
White
3 Participants7 Participants10 Participants
Region of Enrollment
United States
5 Participants8 Participants13 Participants
Sex: Female, Male
Female
4 Participants5 Participants9 Participants
Sex: Female, Male
Male
1 Participants3 Participants4 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
0 / 50 / 8
other
Total, other adverse events
0 / 50 / 8
serious
Total, serious adverse events
0 / 50 / 8

Outcome results

Primary

Alcohol Consequences

Self-report of the Young Adult Alcohol Problems Screening Test (YAAPST). Count of number of consequences experienced. Range: 0-27. Higher scores represent more consequences experienced.

Time frame: 4 weeks following ad-lib.

ArmMeasureValue (MEAN)Dispersion
New PeersAlcohol Consequences0.40 Number of consequencesStandard Deviation 0.74
Close FriendsAlcohol Consequences0.30 Number of consequencesStandard Deviation 0.56
Primary

Alcohol Use

Number of drinks consumed

Time frame: During 1 hour ad-lib period, starting an average of 1 hour after Baseline.

ArmMeasureValue (MEAN)Dispersion
New PeersAlcohol Use3.2 Number of drinksStandard Deviation 0.45
Close FriendsAlcohol Use3.63 Number of drinksStandard Deviation 0.74
Primary

Alcohol Use - Daily Diary

Number of drinks consumed, self-reported the morning after drinking events

Time frame: 4 weeks following ad-lib.

ArmMeasureValue (MEAN)Dispersion
New PeersAlcohol Use - Daily Diary3.8 Number of drinksStandard Deviation 2.57
Close FriendsAlcohol Use - Daily Diary2.61 Number of drinksStandard Deviation 1.7
Primary

Risk-taking

Scores on the Balloon Analogue Risk Task (BART). Scores are calculated by adding the number of pumps for unexploded balloons, with higher scores reflecting greater risk-taking. Range varies - explosions are at a random point between 1 and 128 pumps.

Time frame: Change from baseline (alone) to 20 minutes following Peer Type intervention.

ArmMeasureValue (MEAN)Dispersion
New PeersRisk-taking8.02 Number of pumpsStandard Deviation 9.57
Close FriendsRisk-taking15.29 Number of pumpsStandard Deviation 19.83
Primary

Risk-taking

Scores on the Balloon Analogue Risk Task (BART). Scores are calculated by adding the number of pumps for unexploded balloons, with higher scores reflecting greater risk-taking. Range varies - explosions are at a random point between 1 and 128 pumps.

Time frame: Change from baseline (alone) to immediately following ad-lib, an average of 2 hours after baseline.

ArmMeasureValue (MEAN)Dispersion
New PeersRisk-taking12.83 Number of pumpsStandard Deviation 10.77
Close FriendsRisk-taking28.27 Number of pumpsStandard Deviation 21.11

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026