Work-related stress and cognitive enhancement among university teachers

Abstract

Background:
Working conditions of academic staff have become increasingly complex and occupational exposure has risen. This study investigates whether work-related stress is associated with the use of prescription drugs for cognitive enhancement (CE).

Methods:
The study was designed around three web-based surveys (n1 = 1131; n2 = 936; n3 = 906) to which university teachers at four German universities were asked to respond. It assessed past CE-drug use and the willingness to use CE-drugs as factors influencing future use. Overlap among participants across the surveys allowed for analyses of stability of the results across time.

Results:
Our study suggests a currently very low prevalence of CE-drug use as well as a low willingness to use such drugs. The results showed a strong association between perceptions of work-related stress and all measures of CE-drug use (when controlling for potential confounding factors). They also showed that past use of CE-drugs increased participants' willingness to use them again in the future, as did lower levels of social support. Two different measures showed that participants' moral qualms against the use of CE-drugs decreased their probability of using them.

Conclusions:
The results increase our knowledge about the prevalence of CE-drug use and our understanding of what motivates and inhibits the use of CE-drug.

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Work-related stress and cognitive
enhancement among university
teachers
Constantin Wiegelab, Sebastian Sattlerbcd, Anja S. Göritze & Martin
Diewaldb
a International Institute for Empirical Social Economics,
Stadtbergen, Germany
b Faculty of Sociology, Bielefeld University, Bielefeld, Germany
c Institute for Sociology and Social Psychology, University of
Cologne, Cologne, Germany
d Cologne Graduate School in Management, Economics and Social
Sciences, University of Cologne, Cologne, Germany
e Department of Psychology, University of Freiburg, Freiburg,
Germany
Accepted author version posted online: 09 Mar 2015.Published
online: 10 Apr 2015.
To cite this article: Constantin Wiegel, Sebastian Sattler, Anja S. Göritz & Martin Diewald (2015):
Work-related stress and cognitive enhancement among university teachers, Anxiety, Stress, &
Coping: An International Journal, DOI: 10.1080/10615806.2015.1025764
To link to this article: http://dx.doi.org/10.1080/10615806.2015.1025764
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Work-related stress and cognitive enhancement among
university teachers
Constantin Wiegel
a,b
, Sebastian Sattler
b,c,d
*, Anja S. Göritz
e
and Martin Diewald
b
a
International Institute for Empirical Social Economics, Stadtbergen, Germany;
b
Faculty of
Sociology, Bielefeld University, Bielefeld, Germany;
c
Institute for Sociology and Social Psychology,
University of Cologne, Cologne, Germany;
d
Cologne Graduate School in Management, Economics
and Social Sciences, University of Cologne, Cologne, Germany;
e
Department of Psychology,
University of Freiburg, Freiburg, Germany
(Received 2 February 2013; accepted 1 March 2015)
Background: Working conditions of academic staff have become increasingly complex
and occupational exposure has risen. This study investigates whether work-related stress
is associated with the use of prescription drugs for cognitive enhancement (CE).
Methods: The study was designed around three web-based surveys (n
1
= 1131; n
2
= 936;
n
3
= 906) to which university teachers at four German universities were asked to respond.
It assessed past CE-drug use and the willingness to use CE-drugs as factors influencing
future use. Overlap among participants across the surveys allowed for analyses of
stability of the results across time. Results: Our study suggests a currently very low
prevalence of CE-drug use as well as a low willingness to use such drugs. The results
showed a strong association between perceptions of work-related stress and all measures
of CE-drug use (when controlling for potential confounding factors). They also showed
that past use of CE-drugs increased participants’willingness to use them again in the
future, as did lower levels of social support. Two different measures showed that
participants’moral qualms against the use of CE-drugs decreased their probability of
using them. Conclusions: The results increase our knowledge about the prevalence of
CE-drug use and our understanding of what motivates and inhibits the use of CE-drug.
Keywords: work-related stress; cognitive enhancement; non-medical use of prescrip-
tion drugs; moral perceptions; social support; drug instrumentalization
Introduction
Working conditions in academia have become increasingly complicated, and academics
perceive their work as increasingly stressful (Barkhuizen, Rothmann, & van de Vijver,
2014; Kataoka, Ozawa, Tomotake, Tanioka, & King, 2014; Mark & Smith, 2012). In
Germany, half of full-time professors and about a third of non-professorial staff describe
their job as “very stressful”(Jakob & Teichler, 2011). Similar findings exist for other
countries (e.g., Winefield & Jarrett, 2001). But despite this, research on work-related
stress and coping strategies in academia is scarce (Abouserie, 1996; Brown et al., 1986;
Hogan, Carlson, & Dua, 2002). Our study aims therefore to examine the use of cognitive
enhancement (CE) drugs as a response to work-related stress.
*Corresponding author. Email: sattler@wiso.uni-koeln.de
Constantin Wiegel and Sebastian Sattler contributed equally to the manuscript.
Anxiety, Stress, & Coping, 2015
http://dx.doi.org/10.1080/10615806.2015.1025764
© 2015 Taylor & Francis
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CE can be defined as the augmentation of cognitive performance without medical
indication (Bostrom & Sandberg, 2009; Glannon, 2008; Normann & Berger, 2008). One
frequently discussed means of CE is pharmaceuticals, especially prescription drugs,
which are investigated here. Other pharmaceuticals that are used for CE include over-the-
counter and illegal drugs (e.g., Eickenhorst, Klapp, & Groneberg, 2012; Middendorff,
Poskowsky, & Isserstedt, 2012). These are not investigated here. Prescription drugs
potentially used to enhance cognitive capacities such as memory or attention include
methylphenidate, amphetamine–dextroamphetamine, donepezil, and modafinil (e.g.,
Greely et al., 2008).
With the exception of a few anecdotal reports of professors using modafinil to
enhance productivity or reduce jetlag, little is known about the use of CE-drugs among
academic staff (Sahakian & Morein-Zamir, 2007).
The use of CE-drugs is not without risks, including side effects and long-term health
consequences, such as headaches, high blood pressure, cardiac dysrhythmia, depression,
and addiction (e.g., Greely et al., 2008; Winder-Rhodes et al., 2010). Self-medication
with such drugs can pose increased risks due to the unknown dosage for healthy
individuals, the dangers of counterfeit drugs, and the potentially dangerous combining of
different substances (e.g., Maher, 2008; Sussman, Pentz, Spruijt-Metz, & Miller, 2006).
The present research seeks to understand self-medication with CE-drugs to enhance
cognitive performance by applying a decision-making approach (Gibbons, Gerrard,
Blanton, & Russell, 1998; Gibbons, Houlihan, & Gerrard, 2009; Sattler, Sauer,
Mehlkop, & Graeff, 2013; Sattler & Wiegel, 2013). In seeking to achieve their goals,
individuals face personal and social constraints that facilitate or impede goal attainment.
Similar assumptions can also be found in the Self-Medication Hypothesis (West, 2005),
which posits that individuals intentionally choose (addictive) drugs in order to reduce
cognitive interference or to deal with certain deficits or psychological problems while
nonetheless bearing in mind the negative aspects of such self-medication (Khantzian,
1997). This hypothesis has been also discussed in the context of CE, since individuals
intentionally enhance their cognitive performance through self-medication while taking into
account the potential health risks (Sattler et al., 2013; Sattler & Wiegel, 2013).
The discussion of instrumentalized psychoactive drug use –in which drug use is seen as
a“functional adaption to modern environments”(Müller & Schumann, 2011) and as a
means of coping with demands (cf. Crutchfield & Gove, 1984)–has been applied to CE-
drug use as well (Sattler et al., 2013; Sattler & Wiegel, 2013). For university teachers, stress
is often a function of the pressure to balance teaching load, research, and administrative
duties within a limited amount of time (Brown et al., 1986). Recently, decreasing job
security, university reorganization, higher self-expectations, and more pressure to secure
funding have also contributed to stress (Hogan et al., 2002; Mark & Smith, 2012; Thorsen,
1996). Current university jobs are comparable to jobs in the business world in their constant
demand for a high level of cognitive and physical performance, whereby employees often
lack time to recover from these pressures (Müller & Schumann, 2011; Weber & Jaekel-
Reinhard, 2000). Consequently, the use of CE-drugs with the aim of reducing fatigue or
increasing mental alertness for work purposes, for example, might be seen as a potentially
beneficial “self-medicating answer to difficulties”(Crutchfield & Gove, 1984, p. 503).
Drug users might use medication to prolong or re-establish desired mental states, such as
feeling alert or being able to focus even after long periods of work (Müller & Schumann,
2011). As work performance suffers due to stress, and individuals attempt to minimize or
C. Wiegel et al.2
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avoid this undesirable effect, we expect CE-drug use to increase accordingly in response.
This expectation is supported by studies of other populations in which stressful working
conditions have been associated with the use of substances such as alcohol and illicit and
prescription drugs (Martin, Blum, & Roman, 1992; Zhang & Snizek, 2003). Accordingly,
we propose the following hypothesis (H):
H1
work-related stress
: The higher the self-perceived work-related stress, the higher the likelihood
of using CE-drugs.
In addition to the relationship between work-related stress and CE-drug use, we also
investigated other factors that might be related to CE-drug use or used for coping with
stress. Based on previous research and theoretical reasoning, we tested several hypotheses
related to the following factors:
Prior CE-drug use: While some people may experiment with drugs only once, others
continue using them for a variety of reasons, such as having had a positive experience (cf.
Müller & Schumann, 2011). Previous research has shown that prior CE-drug use makes
subsequent use more likely (cf. Sattler & Wiegel, 2013) and that prior CE-drug use is
associated with a higher willingness to use CE-drugs again (Sattler, Mehlkop, Graeff, &
Sauer, 2014). The latter finding is consistent with the Theory of Planned Behavior
(Beck & Ajzen, 1991; Ouellette & Wood, 1998), which postulates that past behavior
predicts intentions and future behavior. It can be assumed that CE-drug users have
already reached a decision that corresponds to their preferences, and that decisions are
also influenced by other factors, such as lack of self-control (Beck & Ajzen, 1991; Nagin
& Pogarsky, 2001). If these factors are stable over time, they should continue to affect
subsequent choices similarly. The influence of prior use may be due to the role of
experience and habituation and/or to unobserved characteristics related to a willingness to
use drugs. Moreover, if a CE-drug user’s expectations of a drug’s effects are confirmed,
this behavior might be engaged in repeatedly without additional deliberation (Ouellette &
Wood, 1998). There is also evidence that CE-drug users perceive the side effects of such
substances to be less severe than non-users do (Sattler & Wiegel, 2013). We propose the
following hypothesis:
H2
prior CE-drug use
: Prior CE-drug use increases the likelihood of repeated CE-drug use.
Moral perceptions: Scholars have discussed whether the use of performance-enhancing
medication is an unfair means of achieving success (Bostrom & Sandberg, 2009; Farah
et al., 2004; Greely et al., 2008). Studies have found that many people perceive CE-drug
use as morally problematic, as a form of cheating that not only disadvantages others, but
also puts pressure on them to use such drugs as well (Bell, Partridge, Lucke, & Hall,
2013; Forlini & Racine, 2009). Several studies (Ajzen, 1991; Bachman, Paternoster, &
Ward, 1992; Beck & Ajzen, 1991; Bishop, 1984) have shown that moral perceptions have
a strong impact on decision-making and subsequent behavior. Such moral perceptions can
be seen as “internal controls”(Cochran, Chamlin, Wood, & Sellers, 1999). They
can threaten individuals with feelings of guilt or shame if they behave immorally
(Grasmick & Bursik, 1990). These threats can be perceived by individuals as costly (e.g.,
in terms of reduced self-esteem or psychological discomfort) and deter them from
choosing morally problematic behavior by reducing its expected utility. Previous research
Anxiety, Stress, & Coping 3
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has found that moral qualms reduced respondents’willingness to take CE-drugs (Riis,
Simmons, & Goodwin, 2008; Sattler et al., 2013,2014). We propose the following
hypothesis:
H3
moral perceptions
: The more the use of CE-drugs is perceived as immoral, the less likely
CE-drugs will be used.
Social support: Social support is an important resource that helps people achieve life
goals and deal with the problems of everyday life (House & Kahn, 1985), such as work-
related stress. Several studies report that social support and high quality interactions with
friends and family members help to protect against illicit drug use, alcohol use, and drug
dependency (e.g., Bergen, Gardner, Aggen, & Kendler, 2008; Steptoe, Wardle, Pollard,
Canaan, & Davies, 1996). There are two main types of social support: instrumental
support refers to concrete, tangible assistance in case of material or physical need, and
emotional support provides empathy, concern, and encouragement (House, 1981).
University teachers who perceive themselves as possessing a good deal of social support
might be more successful and satisfied with their lives in general (Cohen & Syme, 1985;
Thoits, 1982) and thus have less incentive to enhance their functioning through CE-drugs.
Social support is also a resource for coping with the demands of everyday life and the
burdens of stressful situations or phases of life. Thus, we assume that CE is a resource or
strategy used to deal with these demands and burdens and thus to compensate for a
deficiency of social support. Accordingly, we hypothesize that university teachers with
low social support are more likely to use CE-drugs than those with high social support:
H4
social support
: Social support decreases the likelihood of CE-drug use.
In summary, in three surveys among German university teachers we test whether higher
work-related stress, prior CE-drug use, lower moral qualms against CE-drug use, and
smaller amount of social support are associated with higher CE-drug use.
Methods
Design
For study 1 of our three web-based surveys, we randomly selected four German universities
and 55 academic disciplines from a list provided by the Federal Statistical Office of all
universities and existing academic disciplines. All teachers listed in the respective
university calendars for the current semester were contacted (Table 1). All teachers (still)
listed in the two subsequent semester calendars of the same universities and academic
disciplines were contacted (again) for study 2 (6 months later) and study 3 (12 months
later). The use of the same sampling procedure for the three studies resulted in overlapping
respondents (see below), but due to retirement, job changes, sabbaticals, etc., several
university teachers contacted in study 1 were not contacted for studies 2 and 3, and instead
replaced by new respondents, such as newly hired colleagues.
University teachers received notification letters explaining the purpose of the study
followed by e-mail invitations sent approximately a week later. Up to two e-mail
reminders were sent. The letters explained that participants could choose one of four
rewards (each worth 5 Euro) at the end of the questionnaire (i.e., a payment via
PayPal, a voucher for an online store, a donation to a local charity, or a donation to a
C. Wiegel et al.4
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global charity). The letter, the e-mail invitations, and the first page of the questionnaire
emphasized that participation in the studies was voluntary and anonymous and that
data security was a priority. A data protection officer allocated a token consisting of
six random letters to every teacher. This token was part of a personal survey link,
which was automatically transmitted to our survey software during participation. It
allowed an anonymous linkage of the responses across the three studies. All
procedures were approved by the legal services of Bielefeld University. Since the
respondents were informed about this procedure, participation can be understood as
implied consent.
Similar response rates (comparable to Blix, Cruise, Mitchell, & Blix, 1994; Daniels &
Guppy, 1992) were achieved in all studies (Table 1). In study 1, we have valid responses
for all variables of 1131 respondents, 936 in study 2 and 906 in study 3.
Linking the data from responding university teachers in more than one study
(n
1∩2
= 429; n
1∩3
= 364; n
2∩3
= 372; n
1∩2∩3
= 219) allowed us to perform tests on
the stability of repeated measures and on the robustness of results across different
measures.
Dependent variables
The prevalence of CE-drug use has been reported to be below 5% among German students
(Franke et al., 2011; Sattler & Wiegel, 2013), but the prevalence among university teachers
Table 1. Study characteristics and descriptive information.
Study 1 2 3
Period of data collection 26 August 2010–
5 October 2010
8 March 2011–
15 April 2011
30 August 2011–
16 October 2011
Sample statistics
Number of contacts 3618 3655 3916
Number of respondents 1460 1402 1399
Response rate (%) 40.36 38.36 35.72
Number of analyzed cases 1131 936 906
Dependent variables
CE Willingness-Scale (M; SD) .37 (.90) –
a
–
a
CE Willingness-Dummy (Yes, %) –
a
11.86 13.58
Prior CE-drug use (Yes, %) .88% –
a
–
a
Independent variables
Work-related stress (M; SD) 2.40 (0.83) 2.53 (.85) 2.49 (.82)
Moral perceptions (version 1; M; SD) –
a
3.65 (2.03) –
a
Moral perceptions (version 2; M; SD) –
a
–
a
4.42 (1.33)
Social support (M; SD) –
a
–
a
2.54 (.50)
Demographic variables
Female (%) 34.57 35.58 33.33
Age (median)
b
36–40 36–40 36–40
High status (%) 16.62 21.41 17.00
Medical/health-related disciplines (%) 11.76 12.07 10.82
a
Not assessed in this study;
b
ranging from 0 = “below 20”;1=“20–25”;2=“26–30”;3=“31–35”;4=“36–
40”;5=“41–45”;6=“46–50”;7=“51–55”;8=“56–60”;9=“61–65”;10=“66–70”to 11 = “71 and above.”
Anxiety, Stress, & Coping 5
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is unknown. It has been postulated, however, that CE-drug use is increasing (e.g., Castaldi
et al., 2012; Farah et al., 2004). One method of determining whether such a trend exists is
measuring respondents’willingness to use CE-drugs. In research on the use of (licit and
illicit) substances, willingness-measures can be seen as proximal antecedents of future
behavior (Gerrard et al., 2006; Gibbons, Gerrard, Blanton, et al., 1998; Gibbons, Gerrard,
Ouellette, & Burzette, 1998). Imperfect correlations between willingness and behavior may
be explained by changes in behavioral restrictions over time (cf. Grasmick & Bursik, 1990).
Willingness-measures have the additional advantage of eliciting fewer refusals to answers
to questions about the willingness to conduct a certain behavior as they are less sensitive
than measures of behavior (e.g., Gibbons, Gerrard, Blanton, et al., 1998).
Willingness to use CE
In study 1, CE-drug use willingness was measured on a scale ranging from 0 = “very
unlikely”to 5 = “very likely”in response to the following question: “Some university
teachers boost their cognitive abilities with the help of prescription drugs, though there is no
medical need (e.g., for mental concentration, memory, or vigilance). Regardless of whether
or not you have done so in the past, can you imagine doing something like that?”(cf. Sattler
& Wiegel, 2013). In studies 2 and 3, we used the same question but with dichotomous
response categories; 0 = “No, I would not do that under any circumstances”;1=“Yes, I
would do that under certain circumstances.”
Prior CE-drug use
Prior CE-drug use was measured in study 1 using the same introduction as for the
willingness-measure and asking: “Have you ever done that?”Five response categories
were provided: 0 = “no, never”;1=“yes, within the last 30 days”;2=“yes, between the
last 30 days and 6 months”;3=“yes, between the last 6 months and 1 year”;4=“yes,
more than 1 year ago.”Due to the low prevalence, we computed a dichotomous variable
indicating no use (0) and use (1).
Independent variables
Work-related stress
All three studies employed the work-related stress-scale developed by Enzmann and
Kleiber (1989) consisting of six items, such as “I often feel overburdened.”Responses
ranged from 1 = “not applicable at all”to 5 = “completely applicable.”Due to the one-
dimensional factorial structure and the good internal consistency of this measure
(Cronbach’sαs in study 1: 0.83; study 2: 0.84; and study 3: 0.83), mean values across
all items were computed (Table 1).
Moral perceptions (two versions)
In study 2, moral perceptions (version 1) regarding CE-drug use were measured using the
question: “How do you personally evaluate the use of prescription drugs to enhance work
performance without any medical necessity?”on a 7-point scale ranging from 0 = “not
correct at all”to 6 = “fully correct”(sample item: “It gives me a bad conscience”
(Sattler et al., 2013). Internal consistency of the scale was good (α= 0.89) and factorial
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structure one-dimensional. To test the robustness of results for moral perceptions, study 3
used another instrument, which referred to the concept of the “oughtness”of social norms
(version 2): “One should take prescription drugs to enhance cognitive performance only if
a physician prescribed them.”Participants responded to three items: “Do you think this
norm is important or not important?”ranging from 0 = “very unimportant”to 6 = “very
important; “How do you evaluate people transgressing the norm?”ranging from 0 =
“very negative”to 6 = “very positive,”reverse coded; and “Do you agree with the
norm?”ranging from 0 = “never”to 6 = “always.”The scale had a satisfactory
consistency (α= 0.76) and a one-dimensional structure, so the mean value was computed.
This instrument refers to the theoretical concept by Lindenberg, Joly, and Stapel (2011,
retracted). It is important to point out that although the third author of this retracted paper
manipulated the data-set without the knowledge of his coauthors, the results of our study
are not affected by this manipulation. However, our operationalization of the norm
variables was guided by this paper. We believe that this operationalization captures the
notion of norms provided by Hechter and Opp (2005).
Social support
In study 3, perceived social support was assessed by using the Berlin Social Support
Scales (Schulz & Schwarzer, 2003). Four items each covered emotional (sample item:
“There is always someone there for me when I need comforting”) and instrumental
support (“There are people who offer me help when I need it”). We used a scale with
anchors 1 = “not at all true,”2=“barely true,”3=“moderately true,”4=“exactly true.”
Factor analysis revealed a one-dimensional structure. The internal consistency was 0.92.
To save space for reporting, we used the combined scale, because similar results were
found when using emotional and instrumental support separately (see supplementary
Table S5).
Prior CE-drug use
In addition to analyzing prior CE-drug use as a dependent variable, which is common in
research on CE-drug use (Franke et al., 2011; Wolff & Brand, 2013), it was also used as
an independent variable to examine whether it is a precondition for the willingness to use
CE-drugs (cf. Sattler et al., 2014; see the list of dependent variables above and H2
prior CE-
drug use
in the introduction).
Demographic variables
Women were coded “1”and men “0.”Age was assessed with 11 categories (see Table 1,
also for the other demographics). We grouped disciplines into either medical and health-
related disciplines (coded “1) or other (“0”). High-status individuals (full and assistant
professors) were coded “1”and all others were coded “0”indicating a lower status.
A correlation matrix of all key study variables can be found in supplementary tables
(see Tables S6a–S6c).
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Statistical analysis
Negative binomial regression models were applied in study 1 to analyze the effects of the
predictors on the CE willingness scale, because of highly skewed responses (skewness =
2.98) and overdispersion (p< .001). In such a case, these models are less likely to
produce biased estimates than ordinary least squares regressions (Long & Freese, 2001).
For these models incidence-rate ratios (IRR) are reported. An IRR greater than 1 indicates
a positive effect of the independent variable on the outcome variable. An IRR smaller
than 1 points to a negative effect, while an IRR equal to 1 indicates no effect.
To analyze the effects of the predictors on the dichotomous measures of willingness to
take CE-drugs (studies 2 and 3), logit regression models (e.g., Long & Freese, 2001) were
applied. For both types of logit analyses, odds ratios (OR) are reported. An OR greater than
1 indicates a positive effect of the independent variable on the outcome variable. An OR
smaller than 1 points to a negative effect, while an OR equaling 1 indicates no effect.
Results
Willingness to use CE-drugs
In study 1, 79.6% of the respondents deemed any personal future use of CE-drugs as very
unlikely (Table 1). The rates of refusal to use CE-drugs were similar across studies 2
(88.1%) and 3 (86.4%). The results indicate that willingness was similar across times of
measurement and different measures.
Furthermore, the overlap of respondents in our series of three studies allowed for
more informative stability tests among respondents. We used the willingness-measures
from earlier studies to test their associations with the willingness-measures in subsequent
studies using logit regression models. If the willingness observed in study 1 increased by
one unit on the 6-point scale, the odds of reporting willingness to use CE-drugs would
have increased by 128% (OR = 2.28, p<.001, N= 429) in study 2 and by 163%
(OR = 2.63; p< .001, N= 364) in study 3. Willingness also increased in study 3
(OR = 25.49, p<.001, N= 372), if university teachers reported being willing to use CE-
drugs in study 2. These results demonstrate the high stability of willingness to use CE-drugs.
In the next step, we investigated factors that potentially influenced this willingness by
applying negative binomial regression models in study 1. We found that an increase of
work-related stress by one unit significantly (p<.001) increased this willingness, by 68%
(IRR = 1.68) (see Model 1 in Table 2 for study 1, Model 3 in Table 2 for study 2, and
Model 1 in Table 3 for study 3). In all models, the effects of work-related stress were robust
against potentially confounding factors. Therefore, H1
work-related stress
was supported. We
also found that prior CE-drug use increased the willingness by a factor of 6.75 (p< .010, see
Model 2 in Table 2), which supports H2
prior CE-drug use
. Furthermore, the inclusion of prior
use was also a test for the robustness of the stress effect because this variable may measure
unobserved influences. We found that the effect of work-related stress remained significant
after controlling for “prior CE use.”Moreover, both measures of moral perceptions were
negatively associated with willingness (for version 1, see Model 4 in Table 2, and for
version 2 see Model 2 in Tab l e 3), thereby supporting H3
moral perceptions
. Furthermore, we
found the hypothesized protective effect of social support, which supports H4
social support
(see Model 3 in Table 3). We also considered a stress-buffering effect of social support
(e.g., Viswesvaran, Sanchez, & Fisher, 1999) on willingness to use CE-drugs, which means
that high social support decreases the effect of work-related stress on willingness. We found
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Table 2. Multiple negative binomial regression models (Models 1 and 2) and multiple logistic regression models (Models 3 and 4) to assess associationsof
work-related stress, gender, age, discipline (medical/health vs. others), professional status, prior CE-drug use, and moral perception (version 1) with willingness
to use CE-drugs.
Study 1 (n=1131) Study 2 (n=936)
Model 1 Model 2 Model 3 Model 4
IRR [95% CI] IRR [95% CI] OR [95% CI] OR [95% CI]
Work-related stress 1.68*** [1.41, 2.00] 1.65*** [1.39, 1.96] 1.65*** [1.29, 2.10] 1.78*** [1.38, 2.30]
Female (=yes) 0.98 [0.73, 1.34] 0.98 [0.72, 1.33] 0.59* [0.37, 0.94] 0.57* [0.35, 0.92]
Age 0.93 [0.87, 1.00] 0.94 [0.88, 1.02] 0.94 [0.85, 1.05] 0.95 [0.85, 1.06]
Medical/health (=yes) 0.93 [0.58, 1.49] 0.98 [0.62, 1.55] 0.87 [0.45, 1.67] 0.96 [0.49, 1.89]
High status (=yes) 1.08 [0.69, 1.67] 1.11 [0.72, 1.70] 0.71 [0.39, 1.27] 0.59 [0.32, 1.08]
Prior CE-drug use (=yes) 6.75** [2.15, 2.12] –
a
–
a
Moral perceptions (version 1) –
a
–
a
0.67*** [0.61, 0.75]
AIC 1694.93 1681.34 669.99 612.76
χ
2
38.70 54.28 23.61 82.84
Note: Model 1 shows that increasing work-related stress increases the willingness to use CE-drugs in study 1. Model 2 shows that prior CE-drug use also increases this willingness.
Model 3 replicates the effect of work-related stress in study 2 and shows a lower CE-drug use willingness among females. Model 4 shows that stronger moral qualms about
CE-drug use (version 1) decrease the CE-drug use willingness.
n, number of observations; IRR, incidence rate ratio; OR, odds ratio; CI, confidence interval; AIC, Akaike information criterion.
a
Not assessed in this study.
*p< .05, **p< .01, ***p< .001.
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no such interaction effect. Due to space limitations, we do not depict and discuss this
finding in detail.
Regarding our demographic variables, women demonstrated lower willingness scores
than men in study 2 (p= .020 in Model 4 in Table 2), while no such effect was found in
study 1 (p= .874 in Model 2 in Table 2) and study 3 (p= .574 in Model 3 in Table 3).
Increasing age reduced willingness to use CE-drugs in study 3 (p= .003 in Model 1) but not
in studies 1 and 2 (p= .271). In all studies, status and academic discipline had no effect.
Prior CE-drug use
Fewer than 1% of respondents reported prior CE-drug use (Table 1). Rare events logit
regression analysis shows that prior CE-drug use was more likely when work-related stress
was higher (OR = 2.04; p= .033), thereby supporting H1
work-related stress
. No gender
difference was found. Older respondents were more likely to report prior CE-drug use
(OR =0.66;p=.046). No statistical analysis could be conducted for discipline and status,
since none of the cases of CE-drug use were reported by medical and health-related
university teachers or the high-status group.
Discussion
Our three interconnected, large studies of German university teachers show that the
prevalence of CE-drug use is very low. The declared willingness to use such drugs in the
future was higher than the current use; this discrepancy was stable over time and robust
across two measures. There may be several reasons for the difference between intake
Table 3. Multiple logistic regression models to assess associations of work-related stress, gender,
age, discipline (medical/health vs. others), status, moral perceptions (version 2), and social support
with willingness to use CE-drugs.
Study 3 (n= 906)
Model 1 Model 2 Model 3
OR [95% CI] OR [95% CI] OR [95% CI]
Work-related stress 1.67*** [1.31, 2.13] 1.66*** [1.305, 2.14] 1.58*** [1.22, 2.04]
Female (=yes) 0.76 [0.49, 1.16] 0.79 [0.50, 1.22] 0.88 [0.56, 1.38]
Age 0.84** [0.75, 0.94] 0.84** [0.75, 0.95] 0.82** [0.73, 0.93]
Medical/health (=yes) 1.37 [0.72, 2.58] 1.37 [0.71, 2.65] 1.40 [0.72, 2.69]
High status (=yes) 1.22 [0.67, 2.22] 1.25 [0.68, 2.32] 1.29 [0.700, 2.39]
Moral perceptions
(version 2)
0.61*** [0.53, 0.70] 0.61*** [0.53, 0.70]
Social support 0.62* [0.42, 0.93]
AIC 698.89 652.14 648.77
χ
2
32.82 81.58 86.94
Note: Model 1 shows that increasing work-related stress increases the CE-drug use willingness in study 3, while
increasing age is associated with a lower willingness. Model 2 shows that stronger moral qualms about CE-drug
use (version 2) also decrease respective willingness. Model 3 shows that increasing social support impedes a
high willingness.
n, number of observations; OR, odds ratio; CI, confidence interval; AIC, Akaike information criterion.
*p< .05, **p< .01, ***p< .001.
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willingness and behavior. For example, university teachers might like to use such
medications but do not have access, or they may not have previously had any reason to
use CE-drugs but would be willing to do so if a reason arose. Some teachers might wait
until more powerful and/or safer medication is available. This assumption is supported by
Franke, Bonertz, Christmann, Engeser, and Lieb (2012), who found that 80% of the
German students investigated would consider using CE-drugs if the drugs did not cause
long-term damage or addiction. Maher (2008) found a prevalence of about 20% in a
population that consisted primarily of scientists from 60 different countries. Thus, the low
prevalence found in our study could be due to the fact that the projected upcoming trend
(Franke et al., 2012) has not yet reached Germany.
Work-related stress has recently increased in universities (Mark & Smith, 2012;
Winefield & Jarrett, 2001). We anticipated that some healthy individuals would consider
meeting these heightened job demands by CE. Using multiple measures of CE in three
studies, we found that higher work-related stress was consistently and robustly associated
with a higher willingness to use enhancers as well as with the prior use of such drugs,
thus supporting H1
work-related stress
.
As in other studies (Sattler et al., 2014; Sattler & Wiegel, 2013), here, too, prior CE-
drug use was shown to promote willingness to use CE-drugs in the future, thus
supporting H2
prior CE-drug use
. This finding may indicate that time-invariant factors (such
as preferences or lack of self-control) that influenced prior decisions also influence
subsequent decisions (cf. Beck & Ajzen, 1991; Nagin & Pogarsky, 2001). Habituation
and/or prior experience might also account for this effect. Further analysis should
investigate the mechanism behind this effect, how much deliberation is involved, and
whether this effect indicates addictive tendencies. In our analyses, we cannot distinguish
between these two possibilities, but the inclusion of prior CE-experience allowed us to
consider potentially unobserved heterogeneity among drug users and non-users.
Furthermore, we found that stronger moral qualms against CE-drugs decreased CE-
drug use willingness, thereby supporting H3
moral perceptions
(Sattler et al., 2014). This finding
might be explained by the effect of internal control and the associated fact that feelings of
shame might arise from violating such moral perceptions (cf. Cochran et al., 1999;
Grasmick & Bursik, 1990). This effect was demonstrated by two different measures for
assessing moral considerations, which indicates the robustness of our results.
We also corroborated H4
social support
: University teachers reporting having less social
support –which is an important resource for achieving life goals, dealing with problems,
and creating well-being –reported greater willingness to use CE-drugs. Therefore, CE-
drug use could be interpreted as a strategy to compensate for this deficiency. No stress-
buffering effect of perceived social support was found, however.
Similar to studies in other samples, results for gender were mixed. While no
associations were found in studies 1 and 3 (cf. Rabiner, Anastopoulos, Costello, Hoyle, &
Swartwelder, 2010; Weyandt et al., 2009), women were less willing to use CE-drugs in
study 2 (cf. McCabe, Knight, Teter, & Wechsler, 2005; Rabiner et al., 2009). One
explanation for the latter finding might be that men tend to engage in risky behavior more
often (e.g., Dohmen et al., 2011) and therefore might be more willing to accept risks
associated with CE-drug use. Furthermore, due to the model of the male breadwinner in
Germany, men might feel greater pressure to succeed at work, which would indicate that
men have stronger incentives to use CE-drugs. But there are also opposing mechanisms.
Due to structural discrimination, women in high-status jobs need to work harder to rise in
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the hierarchy compared to men. Additionally, women are more likely to have double and
triple the amount of chores (work, children, household). Due to inconsistent findings,
gender effects need further empirical investigation.
Younger university teachers more often reported a prior use of CE-drugs in study 1
and were more willing to use CE-drugs in study 3. One can argue that CE is a recent
phenomenon and is therefore more widespread among younger university teachers, who
might be more open to experimentation. Furthermore, younger university teachers might
have stronger incentives than older colleagues to invest in achievement strategies. CE-
drug use is also risky because of potential side effects and long-term health consequences,
and risk-taking generally declines with age (Turner & McClure, 2003). But these
assumptions need to be demonstrated in further studies because age was not related to the
CE-drug use willingness in studies 1 or 2.
The lower professional status group reported more prior drug use, but no difference in
willingness was found between status groups. Because of potentially greater competition
for prospective jobs in the lower professional status group, this group might expect to
gain more from CE compared to the higher status group, who have already reached
prestigious and secure positions. But, even in the German high-status group, there is a
considerable degree of competition for recognition and resources within organizations
and among peers in different organizations, which might account for the equally high
willingness to use CE-drugs reported by low- and high-status groups.
No clear differences were found among academic disciplines. University teachers in
medical and health-related disciplines may have both better access to CE-drugs and more
knowledge about the application of CE-drugs (cf. Franke et al., 2011; Teter, McCabe,
LaGrange, Cranford, & Boyd, 2006), but they may also be better informed about the side
effects and limited enhancement effects in healthy individuals (Husain & Mehta, 2011).
Thus, positive and negative effects may offset each other.
Limitations and future research
With the exception of the measure inquiring about past CE-drug behavior, only
willingness-measures were employed. Previous research has shown that willingness
reliably predicts behavior associated with health risks (Gibbons et al., 2009), and we find
it unlikely that work-related stress would influence reported willingness to use CE-drugs
but not behavior. The prevalence of prior CE-drug use was very low, and the willingness
to use CE-drugs was only moderate. In addition to the above-mentioned explanations,
another methodological explanation may be a response bias due to the topic’s sensitivity.
The willingness question might be perceived as less sensitive because no moral
perception is violated until the drug is actually consumed. This might lead to reporting
higher willingness compared to prior use (cf. Gibbons, Gerrard, Blanton, et al., 1998). An
important risk factor for biased answers is lack of anonymity (Ong & Weiss, 2000). We
employed several measures to minimize socially desirable responding and provided full
anonymity (see Methods). Moreover, web surveys increase reporting of sensitive
information and achieve higher accuracy (Crutzen & Göritz, 2010; Kreuter, Presser, &
Tourangeau, 2008). We recalculated all results after applying multiple imputation
techniques (Royston, 2005) to analyze the impact of dropout and item-non-response for
the investigated variables. Results with imputed data are similar to those with non-
imputed data (see supplementary Tables S1–S3).
C. Wiegel et al.12
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To statistically address the low number of past CE-drug users, rare events logistic
regression models were used. Due to the low prevalence of CE-drug use, huge and costly
data-sets are needed for future investigations on behavior. Therefore, our willingness-
measures are valuable for elucidating trends in CE-drug use.
Response rates indicate that a noticeable share of university teachers chose not to
participate in the study. But our response rates were satisfactory because university
teachers have high opportunity costs for participation. Comparisons of willingness-
measures for all participants in each single study and those who participated in one or
more studies reveal similar results (see supplementary Table S4a); hence, those who did
not participate in more than one study did not alter the measured prevalence. Moreover, the
level of work-related stress is very similar among those who participated once, twice, or
three times (cf. supplementary Tables S4a–S4b). These findings are indicative of random
dropout. Furthermore, we verified that our study outcomes were not biased due to selective
study participation by recalculating all models with sampling weights (Winship & Radbill,
1994) (cf. supplementary Tables S7–S10), since gender proportion and discipline
affiliation were available for the contacted sample. But future studies should investigate
potential biases regarding other variables than gender and academic discipline.
Similarities in the results across studies may have resulted, in part, from stabilities
among persons who participated more than once. In total, 219 teachers participated in all
studies. The data from the repeated participants allowed for several stability tests and
were therefore important to this under-investigated topic. We reanalyzed all models using
only the one-time participants to test whether the results were affected by repeated
participation. These analyses (see supplementary Tables S11–13) produced similar results
in terms of all effect sizes. Due to the resulting smaller sample and consequently
decreased statistical power, however, the effects of perceived social support on
willingness in study 3, and work-related stress and age on prior CE-drug use in study 1
no longer achieved a conventional level of significance (see supplementary Tables S11
and S13).
Implications
Our results illustrate that CE-drug use is less common than sensationalized in the media.
But prevalence may increase under the conditions discussed above. In the framework of
drug instrumentalization (Müller & Schumann, 2011), the effect of work-related stress on
CE-drug use can be understood as a non-addictive, functional adaption to complex,
competitive, fast-changing modern microenvironments by increasing, sustaining, or
restoring work performance. Individuals can perceive CE-drug use as a means of
achieving income, status, mental health, etc. But instrumental drug use can also lead to
addiction and unwanted side effects as well as have long-term health consequences
(Müller & Schumann, 2011).
In societies or (sub-)groups in which CE-drug use is prevalent and harmful, drug
regulation and prevention might be advised, and our results can support such endeavors.
Since several university teachers consider CE-drug use a strategy for coping with stress, it
may be advisable to encourage other psychological treatments and non-pharmacological
means such as sleep, meditation, or physical exercise (Dresler et al., 2013; Sahakian &
Morein-Zamir, 2007; Thoits, 1982) to improved cognitive performance, work–life
balances, and relaxation. The CE willingness-inhibiting effect of social support could
Anxiety, Stress, & Coping 13
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also be utilized for prevention. Universities could provide teachers with increased support
to reduce work-related stress and the consequent instrumentalization of CE-drugs. By
fostering discussions about the moral problems of CE-drug use (e.g., fairness) and
strengthening regulations, the belief that CE-drug use is immoral could be used to impede
willingness to engage in CE (Sattler et al., 2013). Furthermore, prior users and potential
users could be informed about the limited enhancements in healthy individuals through
CE-drugs (Husain & Mehta, 2011) and about the risk of severe side effects (e.g., Greely
et al., 2008; Winder-Rhodes et al., 2010). The inscription of such information into the
semantic drug memory may reduce expectations about the benefits of instrumentalizing
CE-drugs (Müller & Schumann, 2011). Moreover, the supervised and informed use of
safe drugs as well as alternative strategies for maintaining and increasing mental
performance and treating stress could replace risky self-medication (Dubljevic, 2013;
Sahakian & Morein-Zamir, 2007).
Acknowledgments
We would like to thank all the people who helped to conduct this study, especially Dominik Koch,
Ines Meyer, Andrea Schulze, Floris van Veen, and Sebastian Willen. We thank Olaf von dem
Knesebeck for critical comments as well as Siegwart Lindenberg for his discussion of our
application of his moral perception measure. Furthermore, we also thank the two anonymous
reviewers for their insightful comments. The FMER did not influence any interpretations or force
the research team to produce biased results. The views expressed do not necessarily reflect the
policies of the funder. The authors did not receive any research support from public or private actors
in the pharmaceutical sector.
Disclosure statement
No potential conflict of interest was reported by the authors.
Funding
This research was funded by the Federal Ministry of Education and Research [FMER; 01PH08024],
headed by Sebastian Sattler and Martin Diewald). Sebastian Sattler’s research was supported by the
Rectorate Fellowship of the Bielefeld University and by a PostDoc Fellowship [Az. 20.13.0.161] of
the Fritz-Thyssen-Foundation and the Cologne Graduate School in Management, Economics, and
Social Sciences.
Supplemental data
Supplemental data for this article can be accessed here.
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