Social Development Theory

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Personality and Individual Differences

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Self-regulation and bedtime procrastination: The role of self-regulation skills
and chronotype

Romana Kadzikowska-Wrzosek
University of Social Sciences and Humanities Faculty in Sopot, ul. Polna 16/20, 81-745 Sopot, Poland

A R T I C L E I N F O

Keywords:
Bedtime procrastination
Quality of sleep
Self-regulation
Morningness-eveningness
Health

A B S T R A C T

The present study focuses on examining the role of chronotype in the relationship between self-regulation skills
and bedtime procrastination. Two possible models were tested, hypothesizing that eveningness may moderate or
mediate the association between self-regulation abilities and bedtime procrastination. A sample of 304 parti-
cipants completed measures of self-regulation, morningness–eveningness, bedtime procrastination, and sub-
jective indicators of the amount and quality of sleep. The analyses showed that bedtime procrastination was
negatively correlated with hours of sleep and positively correlated with frequencies of perceived insufficient
sleep and daily fatigue. Moreover, bedtime procrastination was negatively related to self-regulation skills and to
morningness. No significant interaction (moderation) effect was found between self-regulation skills and
eveningness. The analysis showed that eveningness partly mediated the relationship between low self-regulation
skills and bedtime procrastination. The results confirm that low self-regulation skills may account for higher
bedtime procrastination, and suggest that this negative effect reveals itself, in part, through enhancing even-
ingness.

1. Introduction

Perceived insufficient sleep has recently grown to become a serious
social problem. Empirical findings from many countries confirm that
the problem affects a large proportion of people, who not only ex-
perience discomfort, such as daytime fatigue and sleepiness, but also
are exposed to other serious effects of sleep insufficiency (Kroese, De
Ridder, Evers, & Adriaanse, 2014; Nowicki et al., 2016; Ogińska, Mojsa-
Kaja, Fafrowicz, & Marek, 2014). Just like objective or actual sleep
insufficiency, perceived insufficient sleep has a significant effect on
physical and mental health, achievement, work safety and efficiency,
and social relationships (Hairston & Shpitalni, 2016). Perceived poor
quality and insufficient amount of sleep are more common than clinical
insomnia and research into this problem may provide important addi-
tional information helpful in understanding the causes of sleep pro-
blems and the significance of sleep for health in the general population
(Benham, 2010; Nowicki et al., 2016).

The prevalence of subjective complaints about poor quality and
insufficient amount of sleep, however, calls for looking at sleep pro-
blems from a different perspective than just the clinical one. Sleep
problems leading to perceived insufficient sleep are often caused by the
lifestyle and negative sleep habits. People’s behavior is a significant
determinant of their health. Apart from the genes, the quality of
healthcare, and the environment, it is behavioral factors that account

for 40% of deaths in developed countries (Benham, 2010). This is why a
large proportion of studies within health psychology focus on ex-
amining the determinants and supporting the positive health effects of
such behaviors as physical activity, healthy diet, following doctor’s
orders, avoiding smoking and drinking, and, recently, also behaviors
enabling healthy sleep (Hagger et al., 2014; Kor & Mullan, 2011; Loft &
Cameron, 2013).

Preliminary evidence confirms that just like other health related
behaviors, the quantity and quality of sleep are related to self-regula-
tion skills. Higher self-regulation skills not only facilitate healthy
eating, systematic physical exercise, and changing bad habits; in-
dividual differences in self-regulation skills are also related to hours of
sleep and daytime fatigue (Hagger, 2010; Kroese et al., 2014; Kroese,
Evers, Adriaanse, & de Ridder, 2016). Research findings also suggest
that poorer self-regulation skills are related to a failure to follow the
principles of sleep hygiene (Kor & Mullan, 2011), whereas improving
the ability to control one’s behavior using intention implementation
imagery may be a good way to develop healthy sleep related habits
(Loft & Cameron, 2013).

According to Duckworth and Steinberg (2015), in order to fully
understand the findings from numerous studies of self-regulation, we
need to make a distinction between the external signs of self-regulation
and its underlying psychological processes. There are two basic groups
of processes that play a significant role in self-regulation: volitional

https://doi.org/10.1016/j.paid.2018.02.015
Received 26 December 2017; Received in revised form 7 February 2018; Accepted 9 February 2018

E-mail address: [email protected].

Personality and Individual Differences 128 (2018) 10–15

Available online 22 February 2018
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processes that facilitate self-regulation, and impulsigenic processes that
undermine self-regulation. When examining the determinants of effec-
tive self-regulation, psychologists show a much stronger focus on vo-
litional skills than impulsigenic tendencies. For instance, from the de-
velopmental perspective, it is often presumed that impulsigenic
tendencies remain constant throughout life and that what changes over
time is volitional skills. In fact, understanding the full picture of factors
determining the efficiency of self-regulation requires taking into ac-
count both processes that facilitate self-regulation and those that make
it difficult (Duckworth & Steinberg, 2015). Self-regulation failure may
result both from weak volitional processes and from powerful im-
pulsigenic processes.

In the context of sleep related behavior, the evening chronotype (or
eveningness) is one of the factors undermining self-regulation. In other
words, sleep problems may result not only from the individual’s low
self-regulation skills (or volitional skills), but also from the fact that
their preferred bedtimes and rise times (related to eveningness) differ
from normative social schedules such as work or school hours. For
example, sleep problems which are common among adolescents are
strongly linked their circadian rhythm shift toward eveningness
(Randler, Fabi, & Kalb, 2017). The delayed sleep-phase syndrome is
significantly more frequent among adolescents (7%–16%) than in the
general population (0,13–0,17%) (Bittencourt, Santos-Silva, De Mello,
Anderson, & Tufik, 2010). Thus, it may be concluded that, in a sense, it
is an internal biological mechanism that makes adolescents go to sleep
late.

1.1. Self-regulation, bedtime procrastination, and insufficient sleep

Self-regulation involves the ability to manage one’s goal-directed
activities. It activates processes through which people manage their
thoughts, emotions, and behavior in ways consistent with their goals.
Every effort to change one’s own internal states and responses may be
regarded as a sign of self-regulation (Baumeister, Schmeichel, & Vohs,
2007; Karoly, 1993; Kuhl, 2000).

Self-regulation skills play a crucial role in the transition from an
intention to behavior consistent with this intention. Hence, poor self-
regulation is considered to be an important factor responsible for the
behavioral gap. One manifestation of intention-behavior inconsistency
is procrastination or delaying an intended action (Howell, Watson,
Powell, & Buro, 2006; Lay, 1986; Stainton, Lay, & Flett, 2000). Pro-
crastination means that the individual has formed an intention, but is
unable to proceed from intention to action. Thus, procrastination does
not result from low motivation, but rather from poor behavior control
mechanisms or low self-regulation (Kuhl, 2000).

It seems that many people have the intention and possibility to sleep
well and sleep enough hours, but they cannot implement this intention
successfully. The failure to successfully move from the intention to
sleep well to taking specific steps that would ensure good sleep may be
seen as one of important factors contributing to chronic sleep depri-
vation in many individuals (Loft & Cameron, 2013).

According to Kroese et al. (2014) delaying bedtime is a relatively
common bad habit contributing to perceived insufficient sleep. Re-
searchers refer to this habit as bedtime procrastination. Delaying bed-
time may be regarded as an example of procrastination, because just
like general procrastination it involves putting off an intended action
(in this case, going to bed), a lack of clear reason for the delay (the
individual could go to sleep but fails to do so), and the procrastinator’s
ability to predict some negative consequences of the delay (such as
feeling tired when having to get up the next morning) (Nauts,
Kamphorst, Poortvliet, Sutu, & Anderson, 2016).

Research shows that this specific type of procrastination, i.e. bed-
time procrastination, is linked to low perceived quality and quantity of
sleep. Delaying bedtime turns out to be a prevalent habit in the general
population, having a significant effect on perceived insufficient sleep
and daytime fatigue. Studies have also confirmed that this particular

form of procrastination (delaying bedtime) is associated both with
general procrastination and with self-regulation (Kroese et al., 2014,
2016; Nauts et al., 2016).

Kroese et al. (2014, 2016) have found that people with poor self-
regulation skills usually go to bed later than they intended and that this
behavior has a significant effect on their subjective experience of in-
sufficient sleep. These negative consequences raise a question: Why do
people engage in bedtime procrastination? Why do they delay bedtime
despite being aware of the negative consequences of this behavior? Just
like research into the causes of general procrastination, studies looking
for the causes of bedtime procrastination have not yet provided a sa-
tisfactory answer (Nauts et al., 2016; Steel, 2007). Low self-control
making the individual give in to current temptations without con-
sidering the long-term consequences of such behavior, does not seem a
satisfactory explanation in this case, because the negative con-
sequences, such as perceived insufficient sleep, will be experienced by
the bedtime procrastinator relatively soon. So perhaps our answer to
the question about why people engage in bedtime procrastination
cannot be limited to low self-regulation skills, but should also include
individual differences in chronotype?

1.2. Self-regulation skills, chronotype, and bedtime procrastination

The term “chronotype” refers to individual differences in circadian
rhythms or, in other words, in the functioning of the human biological
clock. At the psychological level, chronotype is a preference for a spe-
cific time of the day, reflected by objective effectiveness of action and
by mood oscillations (Jankowski, 2014; Stolarski, Ledzińska, &
Matthews, 2013). Chronotype is also linked to individual preferences
for early or late bedtimes and rise times (Jankowski, 2017;Vollmer
et al., 2017; Wittmann, Dinich, Merrow, & Roenneberg, 2006).

Chronotype is determined by biological factors (specific genes),
individual factors (such as gender or age), and environmental factors
(e.g., changes of light and dark) (Randler et al., 2017). However, the
circadian rhythms are also influenced by social synchronizers, such as
social activity, including school schedules or the family life, as well as
other social factors. For example, a study of adolescents which ex-
amined the links between morningness–eveningness, pubertal devel-
opment, and family relationships showed that a strong drive toward
autonomy (independence) and frequent conflicts in the family were the
most significant predictors of eveningness. The effect of family re-
lationships on eveningness turned out to be stronger than the effect of
factors, such as age and pubertal development (Díaz-Morales,
Escribano, Jankowski, Vollmer, & Randler, 2014). Other studies also
confirm that factors related to family functioning contribute to chron-
otype. Women’s chronotype is influenced by pregnancy and by having
children (Leonhard & Randler, 2009), and children’s chronotype is in-
fluenced by the rules of family life, parental attitudes, and sleep pro-
blems experienced by the parents, especially the mother (Bajoghli,
Alipouri, Holsboer-Trachsler, & Brand, 2013; Brand, Gerber, Hatzinger,
Beck, & Holsboer-Trachsler, 2009; Urfer-Maurer et al., 2017). Other
data suggest that following the principles of sleep hygiene or shaping
healthy patterns of sleep related behavior may be effective in pre-
venting the shift toward eveningness in adolescence (Vollmer et al.,
2017). It turns out that regular, though not necessarily very intensive,
physical activity, adhering to earlier bedtimes, and following the basic
rules of sleep hygiene may improve the quality of sleep even in ado-
lescents suffering from serious sleep disorders, such as the delayed
sleep-phase syndrome (Brand et al., 2010; Dewald-Kaufmann, Oort, &
Meijer, 2014; Richardson, Gradisar, Short, & Lang, 2017).

Social jetlag or misalignment of the biological and social clocks is
considered to be the main cause of both sleep problems and other
health issues of evening types. Evening types have to deal with a dis-
crepancy between their preferred times for work and study and
morning-oriented schedules imposed by social rules (Jankowski, 2017;
Vollmer et al., 2017; Wittman et al., 2006). This misalignment makes

R. Kadzikowska-Wrzosek Personality and Individual Differences 128 (2018) 10–15

11

task fulfilment particularly challenging for evening types’ self-regula-
tion capacities. As a consequence, their functioning seems to be largely
dependent on their self-regulation skills. The lower the skills, the more
difficult it is for evening types to regulate their sleep related behaviors.
Evidence shows that evening types are likely to experience such sleep
problems as insufficient sleep, irregular sleep patterns, low sleep
quality, and daytime fatigue (Hairston & Shpitalni, 2016; Vollmer et al.,
2017).

The existing data suggest that perceived sleep quantity and quality
are strongly influenced by bedtime procrastination, which in turn is
linked to self-regulation skills. The lower self-regulation skills, the
stronger the tendency to delay bedtime, and ultimately the higher the
level of perceived sleep insufficiency (Kroese et al., 2014, 2016). An-
other important factor may be eveningness, which undermines self-
regulation of sleep related behaviors.

Consequently, a question arises about whether chronotype may be a
boundary condition of the effect of self-regulation skills on bedtime
procrastination. In other words, is bedtime procrastination dependent
on the chronotype? That would mean that low self-control leads to
bedtime procrastination in evening types, whereas individuals with the
evening chronotype and high self-control do not demonstrate bedtime
procrastination. This idea is supported by research evidence showing
that not all evening types have sleep problems (Tavernier &
Willoughby, 2014).

It should be noted, however, that many studies have found a re-
lationship between chronotype and self-control conceptualized as a
personal disposition. Within the Big Five model of personality, con-
scientiousness is regarded as a trait related to self-regulation or self-
control skills; at the same time, it is conscientiousness that has received
the strongest empirical support as a correlate of chronotype (Stolarski
et al., 2013). What is more, evidence confirms that conscientiousness is
the strongest single predictor of chronotype. Morning types are more
conscientious than evening types (Hogben, Ellis, Archer, & von Schantz,
2007). These findings are consistent with data showing that morning-
ness is also linked to higher perseverance (Tonetti, Fabbri, & Natale,
2009), better self-control (Digdon & Howell, 2008; Milfont &
Schwarzenthal, 2014), and the future temporal orientation, whereas
eveningness turns out to be related to the hedonic present orientation
(Stolarski et al., 2013). Research has also found a negative relationship
between morningness and the so called avoidant procrastination (Díaz-
Morales, Ferrari, & Cohen, 2008) and has demonstrated that in evening
types procrastination may lead to sleep problems (Hairston & Shpitalni,
2016).

The above cited data on the relationship between chronotype and
self-regulation come from correlational studies that cannot determine
the direction of causality. Although most researchers emphasize the
biological determination of chronotype, this does not rule out the in-
fluence of other factors (Díaz-Morales et al., 2014; Randler et al., 2017).
It appears that individual differences in self-regulation skills may be a
significant factor shaping and strengthening people’s chronotype. Poor
self-regulation, on the other hand, may strengthen evening types’ bed-
time and rise time preferences inconsistent with social norms, thus
leading to bedtime procrastination. This would mean that chronotype is
not a moderator, but rather a mediator of the relationship between self-
control and bedtime procrastination.

Whereas the previous research supported the relationship between
self-control skills and bedtime procrastination, the current study is in-
tended to complement this evidence by highlighting the role of even-
ingness as a moderator or mediator of the relationship between low
self-control skills and bedtime procrastination.

1.3. The current study

The current study has two major goals: first, to find out whether the
relationship between bedtime procrastination and perceived sleep
quantity and quality, demonstrated by Kroese et al. (2014, 2016), can

be replicated in a Polish sample; second, to examine whether chron-
otype is a moderator or rather a mediator of the relationship between
low self-regulation skills and bedtime procrastination. It was expected
that, similarly to the studies by Kroese et al. (2014, 2016), bedtime
procrastination would contribute to a lower average number of hours of
night-time sleep, and higher perceived sleep insufficiency and daytime
fatigue. It was also expected that including chronotype in the analyses
would shed some new light on the link between self-regulation and
bedtime procrastination.

2. Method

2.1. Measures

2.1.1. Sleep descriptive and indicators of insufficient sleep
Indicators of sleep, including sleep deprivation, were measured

using measures developed by Kroese et al. (2014, 2016). The partici-
pants were asked to indicate, on average, how many hours they typi-
cally slept during week nights. Hours of sleep were measured by asking
“On average, how many hours a night do you sleep on weekdays?”,
which was answered on a 7-point scale ranging from “ < 5 h”, with increments of 1 h (5–6 h, 6–7 h,…) to “ > 10 h.”

A number of indicators of sleep insufficiency were assessed: ex-
periencing insufficient sleep (“In an average week, how many days do
you feel you have had too little sleep?”), and daytime fatigue (“In an
average week, how many days do you feel tired during the day”). Those
two questions were answered on 5-point scales (never; 1–2 days;
3–4 days; 5–6 days; always).

2.1.2. Bedtime procrastination
Bedtime procrastination was assessed with a 9-item scale that was

created by Kroese et al. (2014)) (Cronbach’s alpha = 0.85). Sample
items are “I go to bed later than I would like to,” and “I find it easy to
quit doing other activities in the evening when it is time to go to bed”
(reverse coded). Questions were answered on a scale from 1 (almost
never) to 5 (almost always).

2.1.3. Morningness-eveningness
The Polish version of the Composite Scale of Morningness (CSM;

Smith, Reilly, & Midkiff, 1989) was used (Jankowski, 2015) to asses
morningness/eveningness. The CSM consists of 13 questions about the
time individuals get up and go to bed, their preferred times for physical
and mental activity, and subjective alertness. Five of the elements of the
scale refer to different times of the day. Sample items are “How alert do
you feel during the first half hour after having awakened in the
morning?” or “At what time in the evening do you feel tired and, as a
result, in need of sleep?”. Each item is rated on a 4- or 5-point scale. The
morningness score is obtained by adding up the item scores and ranges
from 13 (extreme eveningness) to 55 (extreme morningness).

2.1.4. Self-regulation skills
Self-regulation skills were measured using the Action Control Scale

(ACS-90; Kuhl, 1994), the Polish adaptation by Marszał-Wiśniewska
(2002). The study used 2 subscales: AOD/SOD (decision-related action
versus state orientation) and AOF/SOF (failure-related action versus state
orientation). The individual items of the AOD/SOD scale of Kuhl’s
questionnaire describe situations of moderate everyday challenge-re-
lated stress (i.e., related to conflicting, difficult, or tedious goals). The
participant chooses one of two proposed responses that better describes
his or her typical behavior in each situation. A sample item describing
challenge-related stress (AOD/SOD) is: “When I am getting ready to tackle
a difficult problem: a) It feels like I am facing a big mountain that I don’t
think I can climb. b) I look for a way that the problem can be approached in
a suitable manner.” The items of the AOF/SOF subscale of Kuhl’s ques-
tionnaire, in turn, describe situations of moderate everyday threat-re-
lated stress. The individual selects one of two proposed responses that

R. Kadzikowska-Wrzosek Personality and Individual Differences 128 (2018) 10–15

12

better describes his or her typical behavior in each situation. A sample
item describing threat-related stress (AOF/SOF) is: “When I am told that
my work has been completely unsatisfactory: a) I don’t let it bother me for
too long. b) I feel paralyzed.” The higher the scale score, the higher the
individual’s self-regulation skills.

2.2. Participants and procedure

A sample of 304 (71.7% of females) students of B.A., M.A., and
postgraduate courses at two universities in Gdańsk (Poland) vo-
lunteered to participate in the study (mean age = 28.54 years;
SD = 7.97, age range = 18–38).The study was conducted in small
groups and the participants were invited to complete the questionnaires
in a classroom environment. It took them 20 min to fill in all the
questionnaires. After the survey the participants’ questions were an-
swered and the researchers thanked them for taking part in the study.
Participation in the survey was voluntary, anonymous, and unpaid.

3. Results

Frequencies of hours of sleep, indicators of insufficient sleep and
daily fatigue are reported in Tables 1 and 2. > 20% of the subjects
reported that during the week they slept 6 or fewer hours per night, on
average, and about 30% of the sample said they experienced in-
sufficient sleep and daily fatigue 3 to 4 days a week.

Table 3 contains the means, standard deviations, internal con-
sistency coefficients (Cronbach’s α) and intercorrelations of all the
variables measured. The pattern of correlations between bedtime pro-
crastination and hours of sleep, and insufficient sleep indicators was in
line with expectations. Higher bedtime procrastination is linked to a
lower average number of hours of sleep, higher frequencies of experi-
enced insufficient sleep, and more frequent daytime fatigue. Bedtime
procrastination was negatively related to both morningness and self-
regulation skills. As regards, morningness, it was positively related to
self-regulation skills. In addition morningness and self-regulation skills
were negatively correlated with insufficient sleep indicators. Morn-
ingness and high level of self-regulation skills are linked to a lower
frequencies of experienced insufficient sleep, and less frequent daytime
fatigue. Results of correlation analyses indicated also positive correla-
tion between morningness and age. Results showed also that female
participants reported a higher score on morningness than their male
counterparts, t(146.85) = 2.24, p < 0.05, M = 34.28 (SD = 6.64) and M = 32.15 (SD = 8.01) respectively (Cohen's d = 0.29). Table 4 provides information on the results of regression analyses for bedtime procrastination. Hierarchical multiple regression analysis was performed to assess the impact of gender, age, chronotype, self- regulation skills, and also the interaction between chronotype and self- regulation skills. In the first step, the demographic variables (gender and age) were entered, followed, in the second step, by self-regulation skills. In the third step chronotype was added and in the final fourth step the interaction term (between chronotype and self-regulation skills) was included. The results indicated that the demographic variables did not ac- count for a statistically significant proportion of the variance in bedtime procrastination. Entering self-regulation skills in step 2 resulted in a statistically significant increment in the explained variance, R2 = 0.05, p < 0.001; F(3,301) = 15.43. Similarly, adding chronotype in step 3 significantly improved the model, R2 = 0.14, p < 0.001; F (4,300) = 51.18.The change of the explained variance from the third to fourth model was not significant. Although self-regulation skills and chronotype yielded significant main effects, the interaction term did not reach statistical significance. In other words, the results did not support chronotype as a moderator of the relationship between self-regulation skills and bedtime procrastination. The examination of beta weights indicated that self-regulation skills and chronotype had significant negative beta weights (β = −0.22, p < 0.001 and β = −0.39, p < 0,001, respectively). Thus, low levels of self-regulation skills and eveningness can be predictors of bedtime procrastination. Since the reduction of self-regulation skills' effect upon adding chronotype to the model suggested possible mediation, a bootstrapping procedure (Preacher & Hayes, 2008) was employed. The bootstrapping procedure based on 5000 bootstrapped resamples to estimate BC95% CI for indirect effect was used in order to examine the indirect effect of self-regulation skills on bedtime procrastination through the mediation of chronotype. The SPSS macro ‘indirect’ (Preacher & Hayes, 2008) was used. The bootstrapped unstandardized indirect effect was −0.011, and the 95% confidence interval ranged from −0.0203 to −0.0033. Thus, the effect of self-regulation skills on bedtime procrastination was par- tially mediated by chronotype. The relationships are illustrated in Fig. 1. The results demonstrated that a lower level of self-regulation skills was significantly associated with eveningness, which, in turn, predicted higher levels of bedtime procrastination. It needs to be acknowledged that the conducted mediational ana- lyses do not determine the casual relationship between self-regulation skills and chronotype. In fact, one may also consider the reversed re- lationship in the way that self-regulation skills mediate the relationship between chronotype and bedtime procrastination. Thus, the decision was made to test such a model. The indirect effect was significant, though weaker in comparison to the ones reported above (−0.003, BC95%CI from −0.0068 to −0.0007). 4. Discussion The main goal of the study was to examine the role of chronotype in the relationship between self-regulation skills and a specific type of procrastination – bedtime procrastination. The results demonstrated that bedtime procrastination was related to fewer hours of sleep and to more frequent experiences of insufficient sleep and daily fatigue. This finding is consistent with previous results obtained by Kroese et al. (2014, 2016). The study also showed that bedtime procrastination was related to both self-regulation skills and chronotype. The analyses de- monstrated that low self-regulation skills were significantly related to Table 1 Frequencies of hours of sleep. On average how many hours a night do you sleep during the week? Frequency % Cum % < 5 h 9 2.80 2.80 5–6 h 62 19.40 22.80 6–7 h 96 30 52.20 7–8 h 109 34.10 86.30 8–9 h 36 11.30 97.50 9–10 h 5 1.30 99.10 > 10 h 3 0.90 100

Table 2
Frequencies of insufficient sleep indicators.

How many days in an average week
do you feel you have had to little
sleep

How many days in an average
week do you feel tired during a
day?

Frequency % Cum % Frequency % Cum %

0 28 8.90 8.90 14 4.40 4.40
1–2 days 121 38.30 47.20 126 39.40 43.80
3–4 days 94 29.70 76.90 103 32.20 …