All estimates in this report are annual averages based on combined 2011 to 2014 NSDUH data. Because NSDUH data were combined from multiple years, the estimates that are presented in this report represent annual averages. In the combined 2011 to 2014 NSDUH data, there were about 25,400 college students aged 18 to 22 who participated in the survey, of whom 21,000 were full-time students and 4,300 were part-time students.⁹ These sample sizes represent an annual average of 9.0 million full-time students and 2.0 million part-time students. This report presents the estimated number of first-time substance users on an average day by college enrollment status.¹⁰ Given that there are more full-time college students than part-time college students, the number of full-time college students engaging in substance use for the first time will be higher than the number of part-time college students engaging in substance use for the first time. This is because presenting the estimated number of users on an average day does not standardize the number of users across varying population sizes and, as a result, it is not useful to compare the number of users who are part-time to the number of users who are full-time. The scale used in the graphics differs for full-time and part-time college students, reflecting the difference in the overall population sizes for both groups. 

Part-Time College Students

For part-time college students, 1.1 million (56.4 percent of this population) drank alcohol in the past month, with 707,000 engaging in binge drinking and 207,000 engaging in heavy alcohol use (35.5 and 10.4 percent, respectively). Nearly 448,000 part-time college students (22.5 percent) used an illicit drug in the past month.

College is often the time when young people begin to engage in substance use. Findings in this report show that, on an average day, alcohol and marijuana were the substances most frequently initiated by both full-time and part-time college students. Heroin and methamphetamine were the least frequently initiated substances by both populations. Because there are more full-time college students than part-time students, it is not useful to compare the number of full-time and part-time college students who are using substances because the differences between the numbers reflect the varying population sizes rather than the proportion of the populations using (i.e., differences in percentages). However, it is possible to compare the information in the report on the average number of drinks consumed by full-time and part-time students. This comparison revealed that the average number of alcoholic drinks consumed by full-time college students slightly exceeded the average number of drinks consumed by part-time college students on days on which they drank alcohol; however, the levels of binge and heavy alcohol use indicate that this is a concern in both populations. Many full-time and part-time college students engaged in binge drinking and in heavy alcohol use.

Although college affords young people numerous new experiences, neither substance use initiation nor substance abuse are universal college experiences. Providing college students with credible and accurate information about the harm associated with substance use is crucial to prevention. To learn about SAMHSA’s efforts to promote behavioral health among students and prevent substance use, go to htttp://www.samhsa.gov/school-campus-health/.

1. United States Census Bureau. (2014). Table 5. Type of college and year enrolled for college students 15 years old and over, by age, sex, race, attendance status, control of school, and enrollment status: October 2014. In Current Population Survey October 2014—Detailed tables. Retrieved from http://www.census.gov/hhes/school/data/cps/2014/tables.html
2. Center for Behavioral Health Statistics and Quality. (2015). Results from the 2014 National Survey on Drug Use and Health: Detailed tables. Rockville, MD: Substance Abuse and Mental Health Services Administration.
3. Substance Abuse and Mental Health Services Administration. (2006, January). A comprehensive plan for preventing and reducing underage drinking. Retrieved from http://www.stopalcoholabuse.gov/media/pdf/underagerpttocongress.pdf.
4. National Institute on Drug Abuse. (2012, November). Medical consequences of drug abuse. Retrieved from http://www.drugabuse.gov/related-topics/medical-consequences-drug-abuse
5. NSDUH is the nation's primary source of information on the prevalence of illicit drug use among the civilian, noninstitutionalized population aged 12 or older, and it also provides estimates of alcohol and tobacco use and mental health problems. Begun in 1971 and conducted annually since 1990, NSDUH is sponsored by SAMHSA and collects data from a nationally representative sample of the population aged 12 or older. NSDUH data are collected through face-to-face, computer-assisted interviews at the respondent's place of residence. Items on sensitive topics such as drug use are self-administered to ensure privacy and promote accurate reporting.
6. Respondents were classified as full-time college students if they reported that they were in their first through fourth years (or higher) at a college or university and that they were enrolled full time. Respondents were classified as part-time college students if they reported that they were in their first through fourth years (or higher) at a college or university and that they were not enrolled full time. Respondents who were on break were considered to be enrolled if they intended to return to college or university when the break ended.
7. In NSDUH, a "drink" is defined as a can or bottle of beer, a glass of wine or a wine cooler, a shot of liquor, or a mixed drink with liquor in it. Times when respondents had only a sip or two from a drink are not considered to be alcohol consumption.
8. Nonmedical use is defined as the use of prescription-type drugs not prescribed for the respondent by a physician or used only for the experience or feeling they caused. Nonmedical use of any prescription-type pain reliever, sedative, stimulant, or tranquilizer does not include over-the-counter drugs. Nonmedical use of stimulants includes methamphetamine use.
9. Data on full-time college students aged 18 to 22 in this report vary from data in a recently published report on monthly variation in initiation of substance use among full-time college students aged 18 to 22. The current report uses combined 2011 to 2014 data based on an estimated annual average of 9.0 million full-time college students aged 18 to 22, while the previous report used combined 2002 to 2013 data based on an estimated annual average of 8.6 million full-time college students aged 18 to 22. The variations in the years of data utilized result in generally minor differences in estimates. www.samhsa.gov/data/sites/default/files/report_2049/ShortReport-2049.pdf.
10. The number of young adults who used alcohol or illicit drugs "on an average day" is calculated by summing the weighted past month frequency of use (0 to 30 days) for each respective substance and dividing by 30. The number of young adults who used alcohol, cigarettes, or illicit drugs for the first time in the past year "on an average day" is calculated by summing the weighted counts of respondents who both initiated substance use in the past year and were calculated to be between the ages of 18 and 22 at the time of first use and dividing by 365. The average number of cigarettes smoked or alcoholic drinks consumed per day in the past month among past month users is calculated using a weighted average or mean of the number of cigarettes or drinks reported by past month users.

Lipari, R.N., & Jean-Francois, B. A Day in the Life of College Students Aged 18 to 22: Substance Use Facts​. The CBHSQ Report: May 26, 2016. Center for Behavioral Health Statistics and Quality, Substance Abuse and Mental Health Services Administration, Rockville, MD.