Addictive Behaviors 39 (2014) 1100–1105
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Addictive Behaviors
Do negative stimulant-related attitudes vary for prescription stimulants and cocaine among college students? Alison Looby a,⁎, Kyle T. Kassman a, Mitch Earleywine b a b
University of North Dakota, Department of Psychology, 319 Harvard Street, Grand Forks, ND 58202, USA University at Albany, State University of New York, Department of Psychology, 1400 Washington Avenue, Albany, NY 12222, USA
H I G H L I G H T S • We examined negative attitudes for prescription stimulants and cocaine. • Attitudes about cocaine were more negative than for prescription stimulants • Less negative attitudes predicted nonmedical prescription stimulant use (NPS)
a r t i c l e
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Available online 12 March 2014 Keywords: Attitudes Cocaine Nonmedical prescription stimulant use Prevention
a b s t r a c t Nonmedical prescription stimulant use (NPS) has become an increasing problem for college students across the United States. Many engage in NPS due to the belief that their academic functioning will improve — a belief that rarely extends to other illicit stimulants. Because positive attitudes toward substances potentially predict the maintenance of current and future use, the aim of the current study was to directly compare attitudes toward different stimulants of abuse (prescription stimulants and cocaine) to ascertain whether attitudes were generally more positive as a function of both drug and drug user type. Ninety-one participants completed a brief attitudinal index assessing attitudes for both prescription stimulants and cocaine. Participants held stronger positive attitudes toward prescription stimulants than cocaine on a variety of items. NPS users reported more positive attitudes toward prescription stimulants than both nonusers and cocaine users. Nonusers reported more negative cocaine-related attitudes than cocaine users and polydrug users (users of both prescription stimulants and cocaine). Intervention programs may benefit from highlighting the negative consequences of NPS, particularly by way of comparisons to cocaine. Doing so may heighten awareness on the overlap of adverse outcomes resulting from use between these stimulants. © 2014 Elsevier Ltd. All rights reserved.
1. Introduction Over the past decade, nonmedical prescription stimulant use (NPS; e.g., methylphenidate, amphetamine/dextroamphetamine) has become an increasing problem across university campuses nationwide. In 2008, the lifetime prevalence rate of NPS among Americans over the age of 12 years was 8.5%, with 12.3% of Americans between the ages of 21 and 25 years reporting lifetime use (Substance Abuse & Mental Health Services Administration, 2009). American college-aged students are 176% more likely than non-students of the same age to engage in NPS (Herman-Stahl, Krebs, Kroutil, & Heller, 2007). A recent review indicates that past-year prevalence rates among college students range from 5% to 35% depending on the geographic location of the school (Wilens et al., ⁎ Corresponding author at: University of North Dakota, Department of Psychology, 319 Harvard Street, Stop 8380, Grand Forks, ND 58201, USA. Tel.: +1 701 777 3451; fax: +1 701 777 3454. E-mail address: [email protected] (A. Looby).
http://dx.doi.org/10.1016/j.addbeh.2014.03.012 0306-4603/© 2014 Elsevier Ltd. All rights reserved.
2008). Moreover, approximately 4% to 11% of college students have engaged in NPS over the past year (Garnier-Dykstra, Caldeira, Vincent, O'Grady, & Arria, 2013). A common motive for NPS among college students is to augment their partying experience and to feel high (Arria & DuPont, 2013). Another frequently cited reason is to enhance attention and/or to study more efficiently via the belief that these drugs directly enhance cognitive ability (Franke, Lieb, & Hildt, 2012). Although these medications are efficacious for improving attention and focus in those diagnosed with attention-deficit/hyperactivity disorder (ADHD), past research indicates that those using prescription stimulants without an ADHD diagnosis are likely not receiving the same cognitive benefits (e.g., Mintzer & Griffiths, 2007; Silber, Croft, Papafotiou, & Stough, 2006; Volkow et al., 2008), though use may be maintained through expectancy-related placebo effects (Looby & Earleywine, 2011; Mommaerts et al., 2013). Methylphenidate (MPH; i.e., Ritalin) produces subjective effects similar to those seen in other illicit stimulant drugs, such as cocaine. For
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example, feelings of euphoria, stimulation, and alertness have been reported following MPH administration in individuals without ADHD (Heil et al., 2002; Rush & Baker, 2001; Stoops, Lile, Fillmore, Glaser, & Rush, 2005). Cocaine users report similar subjective effects following administration of MPH as they do after cocaine administration, such as feeling good and experiencing increases in motivation, the willingness to use again, and to expend resources to obtain the drug (Rush & Baker, 2001). Additionally, MPH has a similar structural profile to that of cocaine (Hoffman & Lefkowitz, 1996) and its actions at the dopamine transporter mirror those of cocaine (Ritz, Lamb, Goldberg, & Kuhar, 1987). Common motives for cocaine use include mood improvement, enhancing alertness, social facilitation, and to get high (Boys, Marsden, & Strang, 2001). Cocaine use is also a strong risk factor associated with NPS among adolescents (Schepis & Krishnan-Sarin, 2008). Although cocaine and MPH are similar in many ways, NPS rates have steadily increased among college students while cocaine use has declined (e.g., McCabe, Teter, & Boyd, 2006; Smith and Farah, 2011), potentially due to differences in reinforcing effects, motivations for use of each drug, and perceived harm of each drug. According to the Monitoring the Future (MTF) survey nearly a decade ago (Johnston, O'Malley, Bachman, & Schulenberg, 2005), lifetime prevalence of cocaine use among college students and young adults between the ages of 19–30 was 14.9% in 2004. In the same sample, past-year cocaine use was 6.5%, while past-year MPH use was 2.4%. More recently, the 2012 MTF survey (Johnston, O'Malley, Bachman, & Schulenberg, 2013) revealed that lifetime prevalence of cocaine use among college students was 5.1%. Pastyear cocaine use among college students was down to 3.1%, while pastyear nonmedical amphetamine/dextroamphetamine (i.e., Adderall) use was 9.0%. Thus, it appears that college students are currently using prescription stimulants at greater rates than cocaine. This shift in usage rates may stem from desired increases in cognitive performance in the academic realm, which is not a motive associated with cocaine use. NPS rates may also be on the rise due to the perceived safety of using prescription stimulants given their status as a prescription medication and that they are prescribed by doctors. College students appear to view prescription stimulants as both less harmful and dangerous than cocaine (Judson & Langdon, 2009), which may explain, in part, the increase in rates of NPS. However, NPS has been coupled with deleterious psychological and physiological outcomes, such as an increased risk of developing dependence, due to the strong potential for abuse (Arria & DuPont, 2010). Other serious consequences of NPS include severe cardiovascular events (e.g., myocardial infarction), sudden death, seizures, or paranoia (Babcock & Byrne, 2000; Braun et al., 2004; Sussman, Pentz, Spruijt-Metz, & Miller, 2006). Unfortunately, many students do not perceive there to be negative consequences associated with NPS. Furthermore, college students may operate under the guise that NPS is innocuous due to commonly held positive associative attitudes, which have been empirically linked with the initiation and maintenance of use (Arria & DuPont, 2013; Bavarian, Flay, Ketcham, & Smit, 2013). Thus, examining the role of stimulant-related attitudes in substance use behavior is warranted. Currently, no research exists that has directly compared prescription stimulant attitudes to attitudes of other illicit stimulants to examine differences in perceived benefits and negative consequences. The purpose of the current study was to assess these attitudes toward NPS and cocaine, as results supporting the notion that students perceive significantly more benefits and significantly fewer negative consequences from NPS compared to cocaine may guide the focus of treatment programs. Broadly, we predicted that the more positive the specific drugrelated attitude, the greater the likelihood of drug use. Since NPS may be viewed as less harmful than cocaine, we examined whether attitudes were more positive for prescription stimulants. Thus, we predicted that positive attitudes would be strongest toward prescription stimulants across all participants, regardless of drug experience. Finally, we examined if attitudes varied as a function of specific drug-related experience. We predicted that nonusers would hold the strongest negative attitudes
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across both stimulants; discrete drug users (i.e., prescription stimulantor cocaine-only users) would hold more positive attitudes toward the specific drug they use; and polydrug users (i.e., users of both cocaine and prescription stimulants) would hold equally positive attitudes toward both drugs. 2. Method 2.1. Participants Ninety-one participants (53% female) completed the current study for partial fulfillment of psychology research credit at a large Northeastern university. Participants reported a mean age of 19.03 (SD = 1.22 years) and 12.69 years of education (SD = 0.92). Most participants were Caucasian (81%), though the sample also included African Americans (8%), Latinos (3%), Asians (3%), persons of mixed race (1%), and 4% classified themselves as “other” or preferred not to answer. 2.2. Procedure Participants were told that the study was designed to examine attitudes toward NPS and cocaine use. Participants indicated whether they had ever engaged in NPS or cocaine use in their lifetime; NPS was defined as use of prescription stimulant medications (e.g., Ritalin, Adderall, Concerta) for recreational purposes or taking it in ways (e.g., insufflated) or dosages not prescribed by a doctor. Participants then completed two 8item measures regarding prescription stimulant- and cocaine-related attitudes (see Table 1). Items were developed based on common motivations for use for each drug, as well as commonly reported negative consequences. Each of the items was formatted on a 10-point Likert scale from 0 (not at all) to 9 (definitely). 2.3. Data analysis All data were analyzed with SPSS version 21.0 for Windows. Pairedsamples t-tests were conducted for each of the 8 attitude items to examine attitudinal differences for cocaine compared to prescription stimulants across all users. A Bonferroni-corrected alpha of .006 was employed for these analyses to account for the multiple comparisons. Logistic regression analyses were then conducted to examine whether attitudes predicted lifetime NPS after controlling for lifetime cocaine use. A Bonferroni-corrected alpha of .006 was again used to account for the multiple predictors. To further examine whether attitudes differed depending on stimulant use history, a multivariate analysis of variance (MANOVA) was conducted to examine composite attitude differences for prescription stimulants and for cocaine among discrete users, polydrug users, and nonusers of both substances. Significant omnibus tests were followed by univariate analyses of variance (ANOVA) using Tukey post-hoc tests to examine differences between user groups. 3. Results Thirty-four participants (37.4%) reported lifetime NPS and 24 participants (26.4%) reported lifetime use of cocaine. Among these users, 45% (18 participants) reported use of both drugs. Fifty-one participants reported lifetime nonuse of both drugs. No differences appeared between users and nonusers of prescription stimulants or cocaine with regard to age, years of education completed, gender, or ethnicity (all ps N .05 for both drugs). General differences between attitudes for prescription stimulants and for cocaine were examined via a series of paired-samples t-tests for each of the 8 attitude items. Table 1 displays means, standard deviations, and effect sizes for each item by drug type. Significant differences were found on all items except for the following item: “Can you understand why someone might take a prescription stimulant/cocaine to party or have fun?” For all other items, participants reported
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Table 1 Comparison of attitudes toward nonmedical prescription stimulant and cocaine use (N = 91). Item
1. Understand using to party/have fun 2. Understand using to study/get work done 3. Wrong to use to party/have fun 4. Wrong to use to study/get work done 5. Use results in health problems 6. Use results in trouble with the law 7. Are addictive 8. Lead to use of other drugs
Prescription Stimulants
Cocaine
M (SD)
M (SD)
t
d
5.54 (2.74) 6.98 (2.29) 5.79 (2.58) 4.19 (2.89) 6.91 (1.98) 7.46 (2.23) 6.66 (2.51) 6.13 (2.71)
4.95 (3.36) 1.71 (2.49) 7.26 (2.31) 8.25 (1.42) 8.64 (0.78) 8.79 (0.69) 8.66 (0.87) 7.97 (1.96)
1.61 14.39⁎ −5.68⁎ −12.71⁎ −8.70⁎ −6.22⁎ −7.95⁎ −7.03⁎
0.17 1.51 −0.60 −1.43 −1.06 −0.84 −1.00 −0.76
Note. Items were answered on a scale of 0 (not at all) to 9 (definitely). ⁎ p b .001.
significantly greater negative attitudes toward cocaine use compared to prescription stimulant use, with the exception of understanding engaging in NPS to study/get work done. These analyses were re-conducted only for participants who reported use of both drugs in order to determine whether direct experience would alter attitudes. The same results were found as in the prior analysis, except that there was no longer a significant difference between drugs on the likelihood of getting into trouble with the law (t(17) = −3.13, p = .134). Given the differences in negative attitudes between drugs, we conducted a logistic regression to examine differences in attitudes between NPS users and nonusers while controlling for lifetime cocaine use. A test of the full model including cocaine use and the 8 attitude items was significant (χ2 = 44.65, df = 9, p b .001), though only cocaine use was a significant individual predictor (β = 2.41, Wald χ2 = 11.51, p b .001). To determine whether a constellation of negative attitudes may instead be more predictive of use than any single belief, items were summed to create an index of prescription stimulant attitudes. Items 1 and 2 were reverse scored, so that higher scores on the attitudes index indicate stronger negative attitudes toward each drug (Cronbach's alpha = 0.75). Additionally, the index scores were standardized in order to assist with interpretation. A logistic regression predicting NPS from the summed standardized negative attitudes while controlling for lifetime cocaine use was statistically significant (χ2 = 31.65, df = 2, p b .001). Lifetime cocaine use remained a significant predictor (β = 2.56, Wald χ2 = 16.71, p b .001), with the odds ratio of 12.90 (95% CI = 3.78–43.94) indicating that cocaine users are nearly 13 times more likely to engage in NPS than non-cocaine users. Lifetime cocaine use alone accounted for 26.5% of the variance in lifetime NPS. The prescription stimulant attitudes index was also a significant predictor (β = −0.92, Wald χ2 = 10.17, p = .001), with the odds ratio of 2.50 (95% CI = 1.42–4.39) indicating that odds of NPS increase by 150% with every 1 standard deviation decrease in summed negative attitudes regarding prescription stimulant use. NPS attitudes accounted for an additional 13.6% of the variance. Together, the two predictors accounted for a large portion of variance in lifetime NPS (Nagelkerke R-square = 0.40). A MANOVA was conducted to examine differences on prescription stimulant- and cocaine-related attitudes among lifetime nonusers, cocaine-only users, prescription stimulant-only users, and polydrug users to ascertain whether attitudes varied as a function of user type. A cocaine attitudes composite score was created in the same manner as the prescription stimulant attitudes index (Cronbach's alpha = 0.63). The multivariate test was significant (F(6, 172) = 5.73, p b .001), as were each of the individual attitude indices. Specifically, the prescription stimulant attitudes index was significant (F(3, 87) = 4.47, p = .006, η2p = 0.13), as was the cocaine attitudes index (F(3, 87) = 6.12, p b .001, η2p = 0.17). Tukey post-hoc tests revealed significant group differences for prescription stimulant attitudes between lifetime nonusers and NPSonly users, such that users reported significantly more positive attitudes compared to nonusers, and also reported substantially more positive attitudes compared to cocaine users, though this was not significant in the
post-hoc test (p = .023). With regard to cocaine attitudes, lifetime nonusers reported significantly more negative attitudes compared to cocaine-only users and polydrug users. There was no difference between nonusers and NPS-only users. Means and standard deviations across user groups for both indices are presented in Table 2. Means and standard deviations across user groups for both indices and for each individual item are presented in Tables 2 and 3, respectively.
4. Discussion The present study sought to examine attitudes toward NPS to determine if they were generally more positive than cocaine-related attitudes. This information may be useful to help identify those who are at risk for NPS and to better understand the increasing prevalence rates and underlying motives for use. Across all attitudinal items, cocaine-related attitudes were generally more negative than prescription stimulant-related attitudes for all participants, regardless of their drug use history. Regarding the specific attitudinal differences between the drugs, participants held relatively strong beliefs that cocaine use may result in more severe health problems, trouble with the law, addiction, and an increased likelihood of using other drugs. Participants also held strong beliefs that using cocaine to party or study was wrong, to a significantly greater extent than they reported to be true for prescription stimulants. Effect sizes for each of the significant differences were large, highlighting the discrepancy in attitudes for both substances. Though consistent with our hypothesis, it is intriguing that participants held significantly more negative attitudes toward using cocaine than prescription stimulants since many of the negative consequences associated with cocaine use overlap with those of prescription stimulants. However, it should be noted that the interpretation of the directionality and magnitude of effects be met with caution. For instance, it is possible that participants' attitudes toward NPS were less negative compared to cocaine due to a lack of adverse experiences following use. Additionally, although participants' attitudes were less negative than cocaine across all attitudinal items, some perceptions of NPS, such as use resulting in health problems, were still relatively negative. A common motive for NPS is academic enhancement, so it is not surprising that participants held such positive attitudes toward using prescription stimulants for academic purposes. However, an interesting finding was that participants held substantially more negative attitudes toward using cocaine to party/have fun, which is a common motive for both drugs. It is peculiar that participants did not condone using cocaine for convivial purposes, but this may be due to the strong overall negative attitudes associated with cocaine use. One possible explanation for the shift in stimulant prevalence rates is that college students may be highly unaware of the negative effects resulting from prescription stimulants due to their medicinal purposes, which may contribute to the perception that they are safe to use. Intervention efforts targeted at reducing NPS rates may be effective if college students are informed of the negative consequences resulting from use and that many of the
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Table 2 User group differences for negative nonmedical prescription stimulant and cocaine attitudes. Factor
NPS attitude score Cocaine attitude score
Nonusers (N)
NPS users (NPS)
Cocaine users (C)
Polydrug users (P)
N = 51
N = 16
N=6
N = 18
M (SD)
M (SD)
M (SD)
M (SD)
45.55 (11.19) 63.02 (8.26)
34.44 (10.97) 62.69 (6.35)
47.00 (8.67) 54.00 (7.24)
40.17 (12.84) 55.67 (6.58)
Pairwise comparisons
N N NPS⁎⁎ N N C⁎; N N P⁎; NPS N C⁎
Note. Higher scores indicate more negative attitudes. Polydrug users refer to participants who reported lifetime use of both cocaine and nonmedical prescription stimulants. NPS = nonmedical prescription stimulants. Pairwise comparisons were corrected using Tukey post-hoc tests. ⁎ p b .05. ⁎⁎ p b .01.
negative effects associated with other stimulants of abuse, specifically cocaine, overlap with NPS. We also examined whether lifetime cocaine use and overall prescription stimulant attitudes were significantly related to lifetime NPS. Cocaine use was strongly associated with NPS, as individuals who reported using cocaine were 12.9 times more likely to engage in NPS than nonusers. Past research has found similar results and that cocaine use is a robust risk factor in predicting NPS (Schepis & Krishnan-Sarin, 2008). Even after controlling for cocaine use, overall prescription stimulant attitudes were significantly associated with NPS. Participants were less likely to engage in NPS the more negative their attitudes toward the medication were. No individual attitude was specifically related to NPS; attitudes were only significantly related to NPS when they were summed. Holding a constellation of negative attitudes seems to be an important determinant in influencing the likelihood of NPS. Thus, it may be important that individuals are educated broadly on the negative consequences of NPS across all categories (e.g., social, trouble with the law, etc.). Finally, we investigated whether composite attitudes of prescription stimulants and cocaine would significantly differ as a function of specific drug-related experience to examine attitudinal strength across different user types. NPS-only users reported the most positive attitudes toward prescription stimulants, which were significantly more positive compared to lifetime nonusers. Regarding cocaine attitudes, cocaine-only users reported significantly more positive attitudes compared to lifetime nonusers. Additionally, nonusers and NPS-only users reported significantly more negative attitudes toward cocaine than polydrug users. These results suggest that there does not seem to be a stimulant crossover effect regarding attitudes. That is, users of cocaine did not necessarily also have
positive attitudes toward prescription stimulants and users of prescription stimulants did not necessarily also have positive attitudes for cocaine. Polydrug users' attitudes toward NPS were not as positive as NPS users' attitudes were. One possible explanation for this attitudinal difference is that NPS users do not perceive there to be negative consequences associated with NPS. Given that participants in our sample held relatively strong positive attitudes for prescription stimulant use, perhaps these attitudes toward NPS remain stagnant as a function of positive expectations stemming from placebo effects (i.e., healthy individuals who engage in NPS may believe that prescription stimulants improve cognitive functioning, thus driving immutable attitudes toward recreational use, even though increases in cognitive performance are likely due to expectations to perform better). On the other hand, the difference in the magnitude of negative attitudes for cocaine was similar between polydrug users and cocaine-only users. Since polydrug users' attitudes toward NPS were substantially negative, this could potentially mean that highlighting the similarities of negative consequences between NPS and cocaine use may result in reducing positive attitudes toward NPS. More research is needed to better understand why these attitudinal differences exist among different user types in order for intervention efforts to be most successful. This study found an exceptionally high rate of NPS, with 37.4% of the sample reporting use. As convenience sampling was employed to recruit participants, it is possible that a self-selection bias may have inflated the prevalence rate of NPS in this sample. However, as participants in this study were recruited from a Northeastern university where prevalence rates are typically higher than in the rest of the country (Graff & Gendaszek, 2002; McCabe, Knight, Teter, & Wechsler, 2005; White, Becker-Blease, & Grace-Bishop, 2006), it may also be possible that our
Table 3 Descriptive Information for nonmedical prescription stimulant and cocaine attitudes by user group. Item
Nonmedical prescription stimulants 1. Understand using to party/have fun 2. Understand using to study/get work done 3. Wrong to use to party/have fun 4. Wrong to use to study/get work done 5. Use results in health problems 6. Use results in trouble with the law 7. Are addictive 8. Lead to use of other drugs Cocaine 1. Understand using to party/have fun 2. Understand using to study/get work done 3. Wrong to use to party/have fun 4. Wrong to use to study/get work done 5. Use results in health problems 6. Use results in trouble with the law 7. Are addictive 8. Lead to use of other drugs
Nonusers (N)
NPS Users (NPS)
Cocaine Users (C)
Polydrug Users (P)
N = 51
N = 16
N=6
N = 18
M (SD)
M (SD)
M (SD)
M (SD)
5.94 (2.74) 6.71 (2.06) 6.75 (2.32) 4.98 (2.89) 7.14 (1.94) 7.16 (2.41) 7.08 (2.00) 6.20 (2.74)
5.88 (2.13) 7.50 (1.83) 4.38 (2.16) 2.56 (2.13) 5.94 (1.77) 6.88 (2.45) 4.81 (3.31) 5.25 (2.29)
5.50 (3.08) 7.83 (2.86) 6.17 (2.32) 4.00 (2.28) 8.50 (1.22) 8.33 (1.03) 7.67 (2.42) 7.67 (1.97)
6.67 (2.95) 7.00 (3.01) 4.22 (2.51) 3.44 (3.01) 6.61 (2.09) 8.56 (1.20) 6.78 (2.46) 6.22 (3.06)
3.80 (3.10) 1.27 (2.10) 7.45 (2.56) 8.22 (1.63) 8.69 (0.73) 8.71 (0.81) 8.78 (0.58) 8.25 (1.71)
4.00 (3.22) 1.13 (1.63) 7.50 (1.97) 8.19 (1.11) 8.63 (0.89) 8.81 (0.75) 8.75 (0.68) 7.94 (1.57)
8.33 (1.03) 2.17 (2.56) 5.50 (2.43) 8.00 (1.26) 8.17 (0.98) 8.83 (0.41) 8.67 (0.52) 7.33 (3.20)
7.89 (2.00) 3.33 (3.45) 7.11 (1.64) 8.50 (1.10) 8.67 (0.77) 9.00 (0.00) 8.22 (1.52) 7.39 (2.40)
Note. Polydrug users refer to participants who reported lifetime use of both cocaine and nonmedical prescription stimulants. NPS = nonmedical prescription stimulants.
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sample reflects a true population with higher rates of NPS. Competitive universities with strict admissions criteria may be causing an increase in NPS rates, although it is not explicitly known why Northeastern universities have higher prevalence rates compared to other geographical locations in the United States. Additionally, our sample was not highly ethnically diverse (e.g., 81% Caucasian). However, NPS is highest among Caucasians (Kroutil et al., 2006; McCabe et al., 2006) and traditional college students (Babcock & Byrne, 2000; Johnston et al., 2005; White et al., 2006), so it is likely that we recruited a relevant sample to this topic. Several limitations of this study warrant cautious interpretation. We did not distinguish between individuals who had used prescription stimulant medications as-prescribed and those who had never used the medication. Therefore, our sample of nonusers may reflect attitudes of both nonusers and medicinal users of prescription stimulants, as well as nonmedical users of other medications. Future research should attempt to examine these groups separately for comparative purposes. The relatively low internal consistency of the cocaine attitudes index may have resulted in specific items not demonstrating significant differences between users and nonusers of cocaine. However, we were still able to observe significant differences on cocaine attitudes, and it is also possible that differences between users and nonusers, as well as differences between discrete users, may be even larger if reliability was increased. Another limitation worth noting was that we used a non-validated self-report index to assess drug-related attitudes. However, items were based on commonly reported motives for and consequences of use for both drugs, and both scales demonstrated adequate internal consistency. Additionally, the sample size was relatively small for some of the groups (i.e., there were only 6 participants in the cocaine-only users group and 18 participants in the polydrug users group, though 26.4% of the sample reported using cocaine) and may not be representative of other groups of NPS users (e.g., high school students). Therefore, our findings on significant attitudinal differences between discrete and polydrug users may have been limited. Another limitation was that only lifetime NPS and cocaine use were measured; future research should examine the relationship between the extent and recency of use and drug-related attitudes. A final limitation was that we did not conduct the analyses prospectively; thus, it is difficult to determine if the attitudinal index may be a valid indicator of future use. Despite these limitations, this study has several strengths. We were able to recruit a proportionately large number of NPS and cocaine users, which allowed for adequate comparison between groups of recreational users and nonusers. The sample is also representative of NPS users in terms of average age, ethnicity, and geographic location. Additionally, this is the first study to directly compare attitudes toward prescription stimulants and cocaine. Given the increasing prevalence rates of NPS among college-age students, this information may be essential in decreasing NPS and associated problems. This research demonstrated that NPS users and nonusers of prescription stimulants significantly differ in the attitudes they hold toward nonmedical use of the medication. As both NPS users and nonusers of prescription stimulants viewed use of the medication to study as generally acceptable, it is possible that beliefs such as this are contributing to the surge in NPS prevalence rates. However, if the negative consequences resulting from NPS are made clear, this could lead to a decrease in prevalence rates. In support of this notion, Looby, De Young, and Earleywine (2013) found negative expectancies toward prescription stimulants to function as a protective mechanism against NPS. Therefore, promoting the negative consequences associated with NPS could prove fruitful in reducing prevalence rates. Our results also confirm that students hold substantially negative attitudes toward cocaine and believe use to be dangerous. Thus, intervention programs for NPS that focus on comparisons to cocaine may successfully alter attitudes, resulting in decreased use. We have additionally created an index of attitudes and risk for use that can reliably predict lifetime NPS above and
beyond the history of cocaine use. This brief index may help identify high-risk individuals and improve prevention and treatment strategies aimed at disproving specific attitudes about the drugs. Role of funding source This research did not receive any financial support.
Contributors AL and ME designed the study and wrote the protocol. AL and KK conducted literature searches and wrote portions of the manuscript. AL conducted the statistical analyses. All authors contributed to and have approved the final manuscript.
Conflict of interest The authors have no conflicts of interest to declare.
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Contents lists available at ScienceDirect
Addictive Behaviors
Do negative stimulant-related attitudes vary for prescription stimulants and cocaine among college students? Alison Looby a,⁎, Kyle T. Kassman a, Mitch Earleywine b a b
University of North Dakota, Department of Psychology, 319 Harvard Street, Grand Forks, ND 58202, USA University at Albany, State University of New York, Department of Psychology, 1400 Washington Avenue, Albany, NY 12222, USA
H I G H L I G H T S • We examined negative attitudes for prescription stimulants and cocaine. • Attitudes about cocaine were more negative than for prescription stimulants • Less negative attitudes predicted nonmedical prescription stimulant use (NPS)
a r t i c l e
i n f o
Available online 12 March 2014 Keywords: Attitudes Cocaine Nonmedical prescription stimulant use Prevention
a b s t r a c t Nonmedical prescription stimulant use (NPS) has become an increasing problem for college students across the United States. Many engage in NPS due to the belief that their academic functioning will improve — a belief that rarely extends to other illicit stimulants. Because positive attitudes toward substances potentially predict the maintenance of current and future use, the aim of the current study was to directly compare attitudes toward different stimulants of abuse (prescription stimulants and cocaine) to ascertain whether attitudes were generally more positive as a function of both drug and drug user type. Ninety-one participants completed a brief attitudinal index assessing attitudes for both prescription stimulants and cocaine. Participants held stronger positive attitudes toward prescription stimulants than cocaine on a variety of items. NPS users reported more positive attitudes toward prescription stimulants than both nonusers and cocaine users. Nonusers reported more negative cocaine-related attitudes than cocaine users and polydrug users (users of both prescription stimulants and cocaine). Intervention programs may benefit from highlighting the negative consequences of NPS, particularly by way of comparisons to cocaine. Doing so may heighten awareness on the overlap of adverse outcomes resulting from use between these stimulants. © 2014 Elsevier Ltd. All rights reserved.
1. Introduction Over the past decade, nonmedical prescription stimulant use (NPS; e.g., methylphenidate, amphetamine/dextroamphetamine) has become an increasing problem across university campuses nationwide. In 2008, the lifetime prevalence rate of NPS among Americans over the age of 12 years was 8.5%, with 12.3% of Americans between the ages of 21 and 25 years reporting lifetime use (Substance Abuse & Mental Health Services Administration, 2009). American college-aged students are 176% more likely than non-students of the same age to engage in NPS (Herman-Stahl, Krebs, Kroutil, & Heller, 2007). A recent review indicates that past-year prevalence rates among college students range from 5% to 35% depending on the geographic location of the school (Wilens et al., ⁎ Corresponding author at: University of North Dakota, Department of Psychology, 319 Harvard Street, Stop 8380, Grand Forks, ND 58201, USA. Tel.: +1 701 777 3451; fax: +1 701 777 3454. E-mail address: [email protected] (A. Looby).
http://dx.doi.org/10.1016/j.addbeh.2014.03.012 0306-4603/© 2014 Elsevier Ltd. All rights reserved.
2008). Moreover, approximately 4% to 11% of college students have engaged in NPS over the past year (Garnier-Dykstra, Caldeira, Vincent, O'Grady, & Arria, 2013). A common motive for NPS among college students is to augment their partying experience and to feel high (Arria & DuPont, 2013). Another frequently cited reason is to enhance attention and/or to study more efficiently via the belief that these drugs directly enhance cognitive ability (Franke, Lieb, & Hildt, 2012). Although these medications are efficacious for improving attention and focus in those diagnosed with attention-deficit/hyperactivity disorder (ADHD), past research indicates that those using prescription stimulants without an ADHD diagnosis are likely not receiving the same cognitive benefits (e.g., Mintzer & Griffiths, 2007; Silber, Croft, Papafotiou, & Stough, 2006; Volkow et al., 2008), though use may be maintained through expectancy-related placebo effects (Looby & Earleywine, 2011; Mommaerts et al., 2013). Methylphenidate (MPH; i.e., Ritalin) produces subjective effects similar to those seen in other illicit stimulant drugs, such as cocaine. For
A. Looby et al. / Addictive Behaviors 39 (2014) 1100–1105
example, feelings of euphoria, stimulation, and alertness have been reported following MPH administration in individuals without ADHD (Heil et al., 2002; Rush & Baker, 2001; Stoops, Lile, Fillmore, Glaser, & Rush, 2005). Cocaine users report similar subjective effects following administration of MPH as they do after cocaine administration, such as feeling good and experiencing increases in motivation, the willingness to use again, and to expend resources to obtain the drug (Rush & Baker, 2001). Additionally, MPH has a similar structural profile to that of cocaine (Hoffman & Lefkowitz, 1996) and its actions at the dopamine transporter mirror those of cocaine (Ritz, Lamb, Goldberg, & Kuhar, 1987). Common motives for cocaine use include mood improvement, enhancing alertness, social facilitation, and to get high (Boys, Marsden, & Strang, 2001). Cocaine use is also a strong risk factor associated with NPS among adolescents (Schepis & Krishnan-Sarin, 2008). Although cocaine and MPH are similar in many ways, NPS rates have steadily increased among college students while cocaine use has declined (e.g., McCabe, Teter, & Boyd, 2006; Smith and Farah, 2011), potentially due to differences in reinforcing effects, motivations for use of each drug, and perceived harm of each drug. According to the Monitoring the Future (MTF) survey nearly a decade ago (Johnston, O'Malley, Bachman, & Schulenberg, 2005), lifetime prevalence of cocaine use among college students and young adults between the ages of 19–30 was 14.9% in 2004. In the same sample, past-year cocaine use was 6.5%, while past-year MPH use was 2.4%. More recently, the 2012 MTF survey (Johnston, O'Malley, Bachman, & Schulenberg, 2013) revealed that lifetime prevalence of cocaine use among college students was 5.1%. Pastyear cocaine use among college students was down to 3.1%, while pastyear nonmedical amphetamine/dextroamphetamine (i.e., Adderall) use was 9.0%. Thus, it appears that college students are currently using prescription stimulants at greater rates than cocaine. This shift in usage rates may stem from desired increases in cognitive performance in the academic realm, which is not a motive associated with cocaine use. NPS rates may also be on the rise due to the perceived safety of using prescription stimulants given their status as a prescription medication and that they are prescribed by doctors. College students appear to view prescription stimulants as both less harmful and dangerous than cocaine (Judson & Langdon, 2009), which may explain, in part, the increase in rates of NPS. However, NPS has been coupled with deleterious psychological and physiological outcomes, such as an increased risk of developing dependence, due to the strong potential for abuse (Arria & DuPont, 2010). Other serious consequences of NPS include severe cardiovascular events (e.g., myocardial infarction), sudden death, seizures, or paranoia (Babcock & Byrne, 2000; Braun et al., 2004; Sussman, Pentz, Spruijt-Metz, & Miller, 2006). Unfortunately, many students do not perceive there to be negative consequences associated with NPS. Furthermore, college students may operate under the guise that NPS is innocuous due to commonly held positive associative attitudes, which have been empirically linked with the initiation and maintenance of use (Arria & DuPont, 2013; Bavarian, Flay, Ketcham, & Smit, 2013). Thus, examining the role of stimulant-related attitudes in substance use behavior is warranted. Currently, no research exists that has directly compared prescription stimulant attitudes to attitudes of other illicit stimulants to examine differences in perceived benefits and negative consequences. The purpose of the current study was to assess these attitudes toward NPS and cocaine, as results supporting the notion that students perceive significantly more benefits and significantly fewer negative consequences from NPS compared to cocaine may guide the focus of treatment programs. Broadly, we predicted that the more positive the specific drugrelated attitude, the greater the likelihood of drug use. Since NPS may be viewed as less harmful than cocaine, we examined whether attitudes were more positive for prescription stimulants. Thus, we predicted that positive attitudes would be strongest toward prescription stimulants across all participants, regardless of drug experience. Finally, we examined if attitudes varied as a function of specific drug-related experience. We predicted that nonusers would hold the strongest negative attitudes
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across both stimulants; discrete drug users (i.e., prescription stimulantor cocaine-only users) would hold more positive attitudes toward the specific drug they use; and polydrug users (i.e., users of both cocaine and prescription stimulants) would hold equally positive attitudes toward both drugs. 2. Method 2.1. Participants Ninety-one participants (53% female) completed the current study for partial fulfillment of psychology research credit at a large Northeastern university. Participants reported a mean age of 19.03 (SD = 1.22 years) and 12.69 years of education (SD = 0.92). Most participants were Caucasian (81%), though the sample also included African Americans (8%), Latinos (3%), Asians (3%), persons of mixed race (1%), and 4% classified themselves as “other” or preferred not to answer. 2.2. Procedure Participants were told that the study was designed to examine attitudes toward NPS and cocaine use. Participants indicated whether they had ever engaged in NPS or cocaine use in their lifetime; NPS was defined as use of prescription stimulant medications (e.g., Ritalin, Adderall, Concerta) for recreational purposes or taking it in ways (e.g., insufflated) or dosages not prescribed by a doctor. Participants then completed two 8item measures regarding prescription stimulant- and cocaine-related attitudes (see Table 1). Items were developed based on common motivations for use for each drug, as well as commonly reported negative consequences. Each of the items was formatted on a 10-point Likert scale from 0 (not at all) to 9 (definitely). 2.3. Data analysis All data were analyzed with SPSS version 21.0 for Windows. Pairedsamples t-tests were conducted for each of the 8 attitude items to examine attitudinal differences for cocaine compared to prescription stimulants across all users. A Bonferroni-corrected alpha of .006 was employed for these analyses to account for the multiple comparisons. Logistic regression analyses were then conducted to examine whether attitudes predicted lifetime NPS after controlling for lifetime cocaine use. A Bonferroni-corrected alpha of .006 was again used to account for the multiple predictors. To further examine whether attitudes differed depending on stimulant use history, a multivariate analysis of variance (MANOVA) was conducted to examine composite attitude differences for prescription stimulants and for cocaine among discrete users, polydrug users, and nonusers of both substances. Significant omnibus tests were followed by univariate analyses of variance (ANOVA) using Tukey post-hoc tests to examine differences between user groups. 3. Results Thirty-four participants (37.4%) reported lifetime NPS and 24 participants (26.4%) reported lifetime use of cocaine. Among these users, 45% (18 participants) reported use of both drugs. Fifty-one participants reported lifetime nonuse of both drugs. No differences appeared between users and nonusers of prescription stimulants or cocaine with regard to age, years of education completed, gender, or ethnicity (all ps N .05 for both drugs). General differences between attitudes for prescription stimulants and for cocaine were examined via a series of paired-samples t-tests for each of the 8 attitude items. Table 1 displays means, standard deviations, and effect sizes for each item by drug type. Significant differences were found on all items except for the following item: “Can you understand why someone might take a prescription stimulant/cocaine to party or have fun?” For all other items, participants reported
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A. Looby et al. / Addictive Behaviors 39 (2014) 1100–1105
Table 1 Comparison of attitudes toward nonmedical prescription stimulant and cocaine use (N = 91). Item
1. Understand using to party/have fun 2. Understand using to study/get work done 3. Wrong to use to party/have fun 4. Wrong to use to study/get work done 5. Use results in health problems 6. Use results in trouble with the law 7. Are addictive 8. Lead to use of other drugs
Prescription Stimulants
Cocaine
M (SD)
M (SD)
t
d
5.54 (2.74) 6.98 (2.29) 5.79 (2.58) 4.19 (2.89) 6.91 (1.98) 7.46 (2.23) 6.66 (2.51) 6.13 (2.71)
4.95 (3.36) 1.71 (2.49) 7.26 (2.31) 8.25 (1.42) 8.64 (0.78) 8.79 (0.69) 8.66 (0.87) 7.97 (1.96)
1.61 14.39⁎ −5.68⁎ −12.71⁎ −8.70⁎ −6.22⁎ −7.95⁎ −7.03⁎
0.17 1.51 −0.60 −1.43 −1.06 −0.84 −1.00 −0.76
Note. Items were answered on a scale of 0 (not at all) to 9 (definitely). ⁎ p b .001.
significantly greater negative attitudes toward cocaine use compared to prescription stimulant use, with the exception of understanding engaging in NPS to study/get work done. These analyses were re-conducted only for participants who reported use of both drugs in order to determine whether direct experience would alter attitudes. The same results were found as in the prior analysis, except that there was no longer a significant difference between drugs on the likelihood of getting into trouble with the law (t(17) = −3.13, p = .134). Given the differences in negative attitudes between drugs, we conducted a logistic regression to examine differences in attitudes between NPS users and nonusers while controlling for lifetime cocaine use. A test of the full model including cocaine use and the 8 attitude items was significant (χ2 = 44.65, df = 9, p b .001), though only cocaine use was a significant individual predictor (β = 2.41, Wald χ2 = 11.51, p b .001). To determine whether a constellation of negative attitudes may instead be more predictive of use than any single belief, items were summed to create an index of prescription stimulant attitudes. Items 1 and 2 were reverse scored, so that higher scores on the attitudes index indicate stronger negative attitudes toward each drug (Cronbach's alpha = 0.75). Additionally, the index scores were standardized in order to assist with interpretation. A logistic regression predicting NPS from the summed standardized negative attitudes while controlling for lifetime cocaine use was statistically significant (χ2 = 31.65, df = 2, p b .001). Lifetime cocaine use remained a significant predictor (β = 2.56, Wald χ2 = 16.71, p b .001), with the odds ratio of 12.90 (95% CI = 3.78–43.94) indicating that cocaine users are nearly 13 times more likely to engage in NPS than non-cocaine users. Lifetime cocaine use alone accounted for 26.5% of the variance in lifetime NPS. The prescription stimulant attitudes index was also a significant predictor (β = −0.92, Wald χ2 = 10.17, p = .001), with the odds ratio of 2.50 (95% CI = 1.42–4.39) indicating that odds of NPS increase by 150% with every 1 standard deviation decrease in summed negative attitudes regarding prescription stimulant use. NPS attitudes accounted for an additional 13.6% of the variance. Together, the two predictors accounted for a large portion of variance in lifetime NPS (Nagelkerke R-square = 0.40). A MANOVA was conducted to examine differences on prescription stimulant- and cocaine-related attitudes among lifetime nonusers, cocaine-only users, prescription stimulant-only users, and polydrug users to ascertain whether attitudes varied as a function of user type. A cocaine attitudes composite score was created in the same manner as the prescription stimulant attitudes index (Cronbach's alpha = 0.63). The multivariate test was significant (F(6, 172) = 5.73, p b .001), as were each of the individual attitude indices. Specifically, the prescription stimulant attitudes index was significant (F(3, 87) = 4.47, p = .006, η2p = 0.13), as was the cocaine attitudes index (F(3, 87) = 6.12, p b .001, η2p = 0.17). Tukey post-hoc tests revealed significant group differences for prescription stimulant attitudes between lifetime nonusers and NPSonly users, such that users reported significantly more positive attitudes compared to nonusers, and also reported substantially more positive attitudes compared to cocaine users, though this was not significant in the
post-hoc test (p = .023). With regard to cocaine attitudes, lifetime nonusers reported significantly more negative attitudes compared to cocaine-only users and polydrug users. There was no difference between nonusers and NPS-only users. Means and standard deviations across user groups for both indices are presented in Table 2. Means and standard deviations across user groups for both indices and for each individual item are presented in Tables 2 and 3, respectively.
4. Discussion The present study sought to examine attitudes toward NPS to determine if they were generally more positive than cocaine-related attitudes. This information may be useful to help identify those who are at risk for NPS and to better understand the increasing prevalence rates and underlying motives for use. Across all attitudinal items, cocaine-related attitudes were generally more negative than prescription stimulant-related attitudes for all participants, regardless of their drug use history. Regarding the specific attitudinal differences between the drugs, participants held relatively strong beliefs that cocaine use may result in more severe health problems, trouble with the law, addiction, and an increased likelihood of using other drugs. Participants also held strong beliefs that using cocaine to party or study was wrong, to a significantly greater extent than they reported to be true for prescription stimulants. Effect sizes for each of the significant differences were large, highlighting the discrepancy in attitudes for both substances. Though consistent with our hypothesis, it is intriguing that participants held significantly more negative attitudes toward using cocaine than prescription stimulants since many of the negative consequences associated with cocaine use overlap with those of prescription stimulants. However, it should be noted that the interpretation of the directionality and magnitude of effects be met with caution. For instance, it is possible that participants' attitudes toward NPS were less negative compared to cocaine due to a lack of adverse experiences following use. Additionally, although participants' attitudes were less negative than cocaine across all attitudinal items, some perceptions of NPS, such as use resulting in health problems, were still relatively negative. A common motive for NPS is academic enhancement, so it is not surprising that participants held such positive attitudes toward using prescription stimulants for academic purposes. However, an interesting finding was that participants held substantially more negative attitudes toward using cocaine to party/have fun, which is a common motive for both drugs. It is peculiar that participants did not condone using cocaine for convivial purposes, but this may be due to the strong overall negative attitudes associated with cocaine use. One possible explanation for the shift in stimulant prevalence rates is that college students may be highly unaware of the negative effects resulting from prescription stimulants due to their medicinal purposes, which may contribute to the perception that they are safe to use. Intervention efforts targeted at reducing NPS rates may be effective if college students are informed of the negative consequences resulting from use and that many of the
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Table 2 User group differences for negative nonmedical prescription stimulant and cocaine attitudes. Factor
NPS attitude score Cocaine attitude score
Nonusers (N)
NPS users (NPS)
Cocaine users (C)
Polydrug users (P)
N = 51
N = 16
N=6
N = 18
M (SD)
M (SD)
M (SD)
M (SD)
45.55 (11.19) 63.02 (8.26)
34.44 (10.97) 62.69 (6.35)
47.00 (8.67) 54.00 (7.24)
40.17 (12.84) 55.67 (6.58)
Pairwise comparisons
N N NPS⁎⁎ N N C⁎; N N P⁎; NPS N C⁎
Note. Higher scores indicate more negative attitudes. Polydrug users refer to participants who reported lifetime use of both cocaine and nonmedical prescription stimulants. NPS = nonmedical prescription stimulants. Pairwise comparisons were corrected using Tukey post-hoc tests. ⁎ p b .05. ⁎⁎ p b .01.
negative effects associated with other stimulants of abuse, specifically cocaine, overlap with NPS. We also examined whether lifetime cocaine use and overall prescription stimulant attitudes were significantly related to lifetime NPS. Cocaine use was strongly associated with NPS, as individuals who reported using cocaine were 12.9 times more likely to engage in NPS than nonusers. Past research has found similar results and that cocaine use is a robust risk factor in predicting NPS (Schepis & Krishnan-Sarin, 2008). Even after controlling for cocaine use, overall prescription stimulant attitudes were significantly associated with NPS. Participants were less likely to engage in NPS the more negative their attitudes toward the medication were. No individual attitude was specifically related to NPS; attitudes were only significantly related to NPS when they were summed. Holding a constellation of negative attitudes seems to be an important determinant in influencing the likelihood of NPS. Thus, it may be important that individuals are educated broadly on the negative consequences of NPS across all categories (e.g., social, trouble with the law, etc.). Finally, we investigated whether composite attitudes of prescription stimulants and cocaine would significantly differ as a function of specific drug-related experience to examine attitudinal strength across different user types. NPS-only users reported the most positive attitudes toward prescription stimulants, which were significantly more positive compared to lifetime nonusers. Regarding cocaine attitudes, cocaine-only users reported significantly more positive attitudes compared to lifetime nonusers. Additionally, nonusers and NPS-only users reported significantly more negative attitudes toward cocaine than polydrug users. These results suggest that there does not seem to be a stimulant crossover effect regarding attitudes. That is, users of cocaine did not necessarily also have
positive attitudes toward prescription stimulants and users of prescription stimulants did not necessarily also have positive attitudes for cocaine. Polydrug users' attitudes toward NPS were not as positive as NPS users' attitudes were. One possible explanation for this attitudinal difference is that NPS users do not perceive there to be negative consequences associated with NPS. Given that participants in our sample held relatively strong positive attitudes for prescription stimulant use, perhaps these attitudes toward NPS remain stagnant as a function of positive expectations stemming from placebo effects (i.e., healthy individuals who engage in NPS may believe that prescription stimulants improve cognitive functioning, thus driving immutable attitudes toward recreational use, even though increases in cognitive performance are likely due to expectations to perform better). On the other hand, the difference in the magnitude of negative attitudes for cocaine was similar between polydrug users and cocaine-only users. Since polydrug users' attitudes toward NPS were substantially negative, this could potentially mean that highlighting the similarities of negative consequences between NPS and cocaine use may result in reducing positive attitudes toward NPS. More research is needed to better understand why these attitudinal differences exist among different user types in order for intervention efforts to be most successful. This study found an exceptionally high rate of NPS, with 37.4% of the sample reporting use. As convenience sampling was employed to recruit participants, it is possible that a self-selection bias may have inflated the prevalence rate of NPS in this sample. However, as participants in this study were recruited from a Northeastern university where prevalence rates are typically higher than in the rest of the country (Graff & Gendaszek, 2002; McCabe, Knight, Teter, & Wechsler, 2005; White, Becker-Blease, & Grace-Bishop, 2006), it may also be possible that our
Table 3 Descriptive Information for nonmedical prescription stimulant and cocaine attitudes by user group. Item
Nonmedical prescription stimulants 1. Understand using to party/have fun 2. Understand using to study/get work done 3. Wrong to use to party/have fun 4. Wrong to use to study/get work done 5. Use results in health problems 6. Use results in trouble with the law 7. Are addictive 8. Lead to use of other drugs Cocaine 1. Understand using to party/have fun 2. Understand using to study/get work done 3. Wrong to use to party/have fun 4. Wrong to use to study/get work done 5. Use results in health problems 6. Use results in trouble with the law 7. Are addictive 8. Lead to use of other drugs
Nonusers (N)
NPS Users (NPS)
Cocaine Users (C)
Polydrug Users (P)
N = 51
N = 16
N=6
N = 18
M (SD)
M (SD)
M (SD)
M (SD)
5.94 (2.74) 6.71 (2.06) 6.75 (2.32) 4.98 (2.89) 7.14 (1.94) 7.16 (2.41) 7.08 (2.00) 6.20 (2.74)
5.88 (2.13) 7.50 (1.83) 4.38 (2.16) 2.56 (2.13) 5.94 (1.77) 6.88 (2.45) 4.81 (3.31) 5.25 (2.29)
5.50 (3.08) 7.83 (2.86) 6.17 (2.32) 4.00 (2.28) 8.50 (1.22) 8.33 (1.03) 7.67 (2.42) 7.67 (1.97)
6.67 (2.95) 7.00 (3.01) 4.22 (2.51) 3.44 (3.01) 6.61 (2.09) 8.56 (1.20) 6.78 (2.46) 6.22 (3.06)
3.80 (3.10) 1.27 (2.10) 7.45 (2.56) 8.22 (1.63) 8.69 (0.73) 8.71 (0.81) 8.78 (0.58) 8.25 (1.71)
4.00 (3.22) 1.13 (1.63) 7.50 (1.97) 8.19 (1.11) 8.63 (0.89) 8.81 (0.75) 8.75 (0.68) 7.94 (1.57)
8.33 (1.03) 2.17 (2.56) 5.50 (2.43) 8.00 (1.26) 8.17 (0.98) 8.83 (0.41) 8.67 (0.52) 7.33 (3.20)
7.89 (2.00) 3.33 (3.45) 7.11 (1.64) 8.50 (1.10) 8.67 (0.77) 9.00 (0.00) 8.22 (1.52) 7.39 (2.40)
Note. Polydrug users refer to participants who reported lifetime use of both cocaine and nonmedical prescription stimulants. NPS = nonmedical prescription stimulants.
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sample reflects a true population with higher rates of NPS. Competitive universities with strict admissions criteria may be causing an increase in NPS rates, although it is not explicitly known why Northeastern universities have higher prevalence rates compared to other geographical locations in the United States. Additionally, our sample was not highly ethnically diverse (e.g., 81% Caucasian). However, NPS is highest among Caucasians (Kroutil et al., 2006; McCabe et al., 2006) and traditional college students (Babcock & Byrne, 2000; Johnston et al., 2005; White et al., 2006), so it is likely that we recruited a relevant sample to this topic. Several limitations of this study warrant cautious interpretation. We did not distinguish between individuals who had used prescription stimulant medications as-prescribed and those who had never used the medication. Therefore, our sample of nonusers may reflect attitudes of both nonusers and medicinal users of prescription stimulants, as well as nonmedical users of other medications. Future research should attempt to examine these groups separately for comparative purposes. The relatively low internal consistency of the cocaine attitudes index may have resulted in specific items not demonstrating significant differences between users and nonusers of cocaine. However, we were still able to observe significant differences on cocaine attitudes, and it is also possible that differences between users and nonusers, as well as differences between discrete users, may be even larger if reliability was increased. Another limitation worth noting was that we used a non-validated self-report index to assess drug-related attitudes. However, items were based on commonly reported motives for and consequences of use for both drugs, and both scales demonstrated adequate internal consistency. Additionally, the sample size was relatively small for some of the groups (i.e., there were only 6 participants in the cocaine-only users group and 18 participants in the polydrug users group, though 26.4% of the sample reported using cocaine) and may not be representative of other groups of NPS users (e.g., high school students). Therefore, our findings on significant attitudinal differences between discrete and polydrug users may have been limited. Another limitation was that only lifetime NPS and cocaine use were measured; future research should examine the relationship between the extent and recency of use and drug-related attitudes. A final limitation was that we did not conduct the analyses prospectively; thus, it is difficult to determine if the attitudinal index may be a valid indicator of future use. Despite these limitations, this study has several strengths. We were able to recruit a proportionately large number of NPS and cocaine users, which allowed for adequate comparison between groups of recreational users and nonusers. The sample is also representative of NPS users in terms of average age, ethnicity, and geographic location. Additionally, this is the first study to directly compare attitudes toward prescription stimulants and cocaine. Given the increasing prevalence rates of NPS among college-age students, this information may be essential in decreasing NPS and associated problems. This research demonstrated that NPS users and nonusers of prescription stimulants significantly differ in the attitudes they hold toward nonmedical use of the medication. As both NPS users and nonusers of prescription stimulants viewed use of the medication to study as generally acceptable, it is possible that beliefs such as this are contributing to the surge in NPS prevalence rates. However, if the negative consequences resulting from NPS are made clear, this could lead to a decrease in prevalence rates. In support of this notion, Looby, De Young, and Earleywine (2013) found negative expectancies toward prescription stimulants to function as a protective mechanism against NPS. Therefore, promoting the negative consequences associated with NPS could prove fruitful in reducing prevalence rates. Our results also confirm that students hold substantially negative attitudes toward cocaine and believe use to be dangerous. Thus, intervention programs for NPS that focus on comparisons to cocaine may successfully alter attitudes, resulting in decreased use. We have additionally created an index of attitudes and risk for use that can reliably predict lifetime NPS above and
beyond the history of cocaine use. This brief index may help identify high-risk individuals and improve prevention and treatment strategies aimed at disproving specific attitudes about the drugs. Role of funding source This research did not receive any financial support.
Contributors AL and ME designed the study and wrote the protocol. AL and KK conducted literature searches and wrote portions of the manuscript. AL conducted the statistical analyses. All authors contributed to and have approved the final manuscript.
Conflict of interest The authors have no conflicts of interest to declare.
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