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10 Health Psychology Update, Volume 26, Issue 1, Spring 2017
Research Paper
‘The Three Good Things’ – The effects of
gratitude practice on wellbeing:
A randomised controlled trial
Siew Tim Lai & Ronan E. O’Carroll
Background: There are mixed ndings concerning the effectiveness of gratitude interventions. This study
investigated a commonly used gratitude-based intervention (‘count-your-blessings’) in promoting physical
and psychological wellbeing in a UK sample.
Methods: A randomised controlled trial to examine the efcacy of a three-week gratitude intervention in
promoting psychological and physical health. 108 healthy participants (aged 18–36) were randomly assigned
to 1 of 2 conditions (gratitude or no-assigned activity). Those in the gratitude condition kept daily gratitude
journals for 21 days. Participants completed self-report measures related to gratefulness, affect, prosociality,
physical and subjective wellbeing. These measures were collected at two time-points (pre- and post-intervention),
three weeks apart. Two separate analyses were conducted for participants who completed the intervention
(Completer analysis) and including those who dropped out (Intention-to-treat analysis [ITT]).
Findings: Completer analysis revealed that the gratitude condition resulted in heightened feelings of
gratefulness. Those in the grateful condition showed greater increases in state gratitude and positive affect,
relative to the control condition, who reported a reduction in wellbeing. Overall, the ITT analysis yielded
essentially the same ndings as the completer analysis.
Discussion: Counting one’s blessings can improve wellbeing and could be incorporated in existing
psychotherapies. This brief and simple intervention warrants further investigation.
Keywords: Gratitude; positive affect; wellbeing; health; positive psychology interventions.
Introduction
Studies that aimed to promote wellbeing have
shown that individuals with positive mental
health hold numerous physical, social and intel-
lectual benets compared to their unhappy
counterparts (Fredrickson, 2001). This
increased emphasis on positive phenomena
has led the United Nation General Assembly
to review the approaches to systematic meas-
urements of happiness at the individual and
national level (Layard, 2013). Although there
are various ways to increase wellbeing, the culti-
vation of gratitude is thought to be the quin-
tessential positive personality trait, allowing
individuals to lead a ourishing life (Wood et
al., 2009).
Conceptualisation of gratitude
Gratitude is considered as both trait
and state. State gratitude is the feeling
of awe, gratefulness and appreciation for
outcomes received (McCullough et al.,
2002). Emmons (2007) characterizes these
experiences as acute, intense and co-occur-
ring with joyful feelings. Trait gratitude is
described as an individual’s predisposition
to experience this state in life (McCullough
et al., 2002).
Theoretically, being thankful in life is
expected to be strongly associated to well-
being. This is explained in the schematic
hypothesis (Wood et al., 2010), which claims
that grateful individuals are more likely to
Health Psychology Update, Volume 26, Issue 1, Spring 2017 11
‘The Three Good Things’ – The effects of gratitude practice on wellbeing: A randomised controlled trial
notice the positivity in life, and this inu-
ences how they interpret their life events
(Wood et al., 2010). Watkins (2004) elabo-
rated that in times of adversity, gratitude
shifts one’s mindset of deprivation to appre-
ciation; this particular interpretative lens
enhances subjective wellbeing. Drawn from
Fredrickson’s (2001) broaden-and-build theory,
positive emotions like gratitude broadens
through thought-action repertoires which
builds a person’s psychosocial and spiritual
resources. The broadening hypothesis is
compatible with aforementioned accounts
of the mechanisms linking gratitude to well-
being. As Fredrickson (2001) suggested, grat-
itude facilitates ‘meaning-nding’ in ordinary
events and within the adversity itself. This
may fuel psychological resilience, leading
to appreciable increases in emotional well-
being over time (Kashdan & Rottenberg,
2010). Although emerging perspectives
complementing this notion have highlighted
the inter-intrapersonal benets of gratitude
(McCullough et al., 2001), the effects of
gratitude on human health identied thus
far are likely just the tip of the proverbial
iceberg.
Empirical research on gratitude and
wellbeing
Emmons and McCullough (2003) employed
a self-guided journal method to determine
the effect of gratitude on wellbeing among
college students. Their ndings revealed
that those who recorded grateful thoughts
had positive results (i.e. increased in posi-
tive emotions, altruistic behaviour and fewer
physical complaints). Grateful contempla-
tion reduces excessive worrying and levels
of depression over time (Wood et al., 2007).
Whilst other research demonstrated grateful
individuals reported less post-traumatic
symptoms when compared to their less
grateful counterparts following a stressful
life-event (Wood et al., 2010).
A meta-analysis has shown that the impact
of gratitude practice on wellbeing and its
efcacy is moderated by various factors
(Wood et al., 2010). For instance, previous
control groups used in gratitude interven-
tion involved downward social comparison,
writing about earliest memories, and listing
hassles. The diverse control conditions may
not generate equal expectancy effects as the
gratitude condition. This makes it problem-
atic to infer the effectiveness of the interven-
tion. Moreover, some studies did not explore
whether gratitude was successfully cultivated
(Sin et al., 2009) leaving doubts to its posi-
tive changes.
To explore these issues, we replicated
Emmons and McCullough’s (2003) study.
We included validated scales (e.g. the Grati-
tude Adjectives Checklist [GAC] and Grati-
tude Dispositional Scales [GQ-6]) to track
the changes in gratitude. A control group
without any assigned activity was used to
minimise expectancy effects, allowing us to
gauge the true effect of the intervention.
We utilised both completer and intention-
to-treat analysis (ITT). Given that the inter-
vention will not be effective for everyone,
we also explored the relationship between
effort and time taken to perform the inter-
vention and outcome.
Predictions
We predict that a grateful contemplation
would result in higher levels of state and
trait gratitude, positive affect and wellbeing.
Participants in the gratitude condition would
score higher on the perception of inter-
personal quality and report fewer physical
complaints compared to participants in the
control condition.
Methods
Design
A three-week experimental randomised
controlled trial (RCT) was employed to
address the research aim. The independent
variable comprised of two experimental
conditions: (1) Gratitude (participants
assigned with gratitude-inducing activity)
and (2) Control (no assigned task). Both
groups were measured at two time points,
12 Health Psychology Update, Volume 26, Issue 1, Spring 2017
Siew Tim Lai & Ronan E. O’Carroll
three weeks apart: (a) Pre-test (prior to inter-
vention); (b) Post-test (immediately after
intervention).
Participants
Eligible participants were students from a
university in the UK, age range 18–21, able to
read and write English; recruited via online
advertisement and the face-to-face approach.
In an effort to minimise unintended vari-
ation in the procedure, both approaches
utilised standard instructions that partici-
pants read themselves.
The study was advertised as ‘A Study on
Human Emotions’ to mask the trial hypoth-
eses. The face-to-face method contains a
set of questionnaires and consent form in
a sealed envelope which were distributed
randomly in the campus. Those who agreed
to participate then signed the consent form
and returned the required documents to
the investigator. For the online recruitment,
interested candidates commenced the study
via a web-link, completion of baseline meas-
ures was considered as informed consent.
A total 108 participants (62 females, 46
males) were recruited and randomised into
either the gratitude (N=51) or the control
(N=57) condition. The average age was 22
years (SD=2.85), with over 65 per cent unem-
ployed university graduates. Almost half
of the sample was White (53.7 per cent),
and the rest was Asia/Pacic Islander (41.7
per cent). The nal analysis included 36
in the gratitude condition and 45 in the
control group, 27 participants (gratitude=15,
control=12) dropped out from the study.
Measures
At baseline participants were asked to provide
demographic information, including age,
sex, education, employment status, and
ethnicity. Participants completed additional
measures relating to gratitude, affect, well-
being, health complaints and perceived
quality of interpersonal relationship at base-
line and 21 days after intervention. All meas-
ures were administered online.
State and dispositional gratitude (GAC
and GQ-6) (McCullough et al., 2002). The
Grateful Adjectives Checklist consists of
three adjectives (appreciative, thankful, and
grateful) to examine participant’s feelings of
state gratefulness on a 5-point Likert scale
(1=not at all, 5=extremely). Scores range
from 3 to 15, higher scores indicates higher
levels of state gratitude.
The Gratitude Dispositional Scales
assesses an individual’s disposition to expe-
rience this state. It has six descriptive items
that is scored on a 7-point Likert scale
(1=strongly disagree, 5=strongly agree).
Scores range from 6 to 42.
Positive and negative affect scale
(PANAS) (Watson, Clark, & Tellegen, 1998).
The PANAS includes 20 affective states rated
on a 5-point Likert scale (1=very slightly,
5=extremely). Scores range from 10 to 50
and higher scores indicate higher levels of
positive or negative emotions experienced.
Warwick-Edinburgh mental wellbeing
scale (WEMWBS) (Tennant el al., 2007). The
WEMWBS is a 14-item questionnaire that
measures mental wellbeing on a 5-point
Likert scale (1=none of the time, 5=all of
the time). Scores vary from 14 to 70, higher
scores indicates higher levels of mental well-
being.
Physical symptoms checklist (Emmons &
McCullough, 2003). A list of 13 physical symp-
toms (e.g. runny/congested nose, headache
and etc.) requires participants to indicate
whether they had experienced these symp-
toms for the past two weeks. Participant’s
perceived health status was obtained by
summing up the symptoms experienced.
Quality of relationship with signicant
others (Martinez-Marti et al., 2010). Four
items rated on a 4-point Likert scale (1=not
at all, 4=a great deal) was used to assess
the participant’s quality of relationship with
close others.
An exploratory effort and motivation form
was given to participants at post-intervention.
The form included questions developed by
Odou et al. (2013) to assess participant’s
Health Psychology Update, Volume 26, Issue 1, Spring 2017 13
‘The Three Good Things’ – The effects of gratitude practice on wellbeing: A randomised controlled trial
effort (e.g. on average how many minutes
did it take you to complete your activity?)
and motivation (e.g. how motivated did you
feel about doing the activity?) on a 5-point
Likert scale (1=not at all, 5=extremely).
To measure adherence for the assigned
activity, participants were asked to answer a
question on a 7-point Likert scale (1=never,
7=daily). The question was ‘We understand
that at some point there are circumstances that
cause you to be unable to carry out the assigned
activity as intended. We appreciate your honesty to
indicate throughout these 21 days, how often you
think you actually did the assigned activity.’
Procedure
Participants who provided consent and
completed baseline measures were assigned
an identication number that can only be
identied by the researcher. They were then
randomised to the experimental condi-
tions using a computer software package
(Urbaniak & Plous, 2013). After randomi-
sation, specic instructions were given to
participants according to their respective
groups. Participants in both conditions were
contacted by mail before, during and after
21 days of the intervention to complete their
online measures.
The gratitude condition received an
instruction to cultivate gratefulness for
21 days. The information to perform the
gratitude-inducing activity incorporated
instructions from both studies (Emmons
& McCullough, 2003; Martinez-Marti et al.,
2010). The instructions were:
‘There are many things in our lives, both large
and small, that we might consider as a form of
blessing. It could even be those who help us to reach
our goals, or just make our lives easier with small
details. If we try to put ourselves in their shoes,
appreciate their efforts, and notice the voluntary
nature of their acts, we have a good reason to feel
grateful. Please think of today and write down
three things in your life that you are grateful for.’
They were required to record their
daily grateful thoughts in a journal that was
provided. To encourage adherence they
were invited to submit their journal on an
appointed date after post-test. Participants in
the control condition were not assigned any
activity, but to complete the same measures
given to the gratitude condition.
Analytic plan
Descriptive statistics were generated for
the total sample. Missing cases (<5%) were
addressed with means substitution. Two-way
mixed ANCOVA was used to test for change
over time among participants who completed
the intervention versus control. Effects were
calculated for time and time × group interac-
tions. Covariates were ethnicity and gender
because randomisation revealed unequal
distributions of these variables in the exper-
imental conditions. Pearson’s correlation was
used to explore the relationship between indi-
vidual’s engagement (e.g. effort and motiva-
tion) and the effects of gratitude practice.
Two analyses were conducted – Completer
analysis (participants who completed the
intervention) and Intention-to-treat (ITT)
analysis (included participants who dropped
out). The ITT was carried out using the
last observation carried forward (LOCF)
method. For all hypotheses testing, it is
expected that participants in the gratitude
condition would have better outcomes than
the control condition.
Results
We only present the main ndings for
completer analysis (Table 1) because all
measures yielded essentially the same results
as the ITT analysis.
Dispositional and state gratitude
The main effect of group on disposi-
tional gratitude scores was signicant [F(1,
77)=4.892, p=.030, partial η2=.060]. The
condition × time interaction for disposi-
tional gratitude was also signicant [F(1, 77)
=4.84, p=.044, partial η2 =.052]. Dispositional
gratitude decreased in the control condition
relative to the gratitude intervention (see
Table 1).
14 Health Psychology Update, Volume 26, Issue 1, Spring 2017
Siew Tim Lai & Ronan E. O’Carroll
The condition × time interaction for
state gratitude was signicant [F(1, 77)=8.48,
p=.005, partial η2=.099]. State gratitude
increased in the gratitude intervention (see
Figure 1). Thus, those who practiced grat-
itude had higher levels of state and trait
gratitude relative to the control condition.
Positive affect
The condition × time interaction for positive
affect was signicant [F(1, 77)=4.90, p=.030,
partial η2 =.060] – see gure 2.
Wellbeing
The completer analysis for the condition ×
time interaction for well-being measure was
of borderline signicance (p=.053); however,
the results for the ITT analysis was signicant
[F(1, 104)=4.73, p=.032, partial η2=.043].
There was greater drop in wellbeing in the
control condition (see Table 1).
Physical health
Table 1 showed no difference was observed
for reported physical illness (p=.055) in both
experimental conditions.
Perceived quality of interpersonal
relationships
For participants in the gratitude condition,
the perception of relationship quality with
others was not signicantly different (p=.871)
than the control condition (see table 1).
Individual differences in practicing
gratitude
Motivation and effort were positively corre-
lated with increase in state gratitude, moti-
vation (r=.333, p=.047) and effort (r=.414,
p=.012). Participants with greater motivation
were more likely to adhere to the activity
(r=.321, p=.046) and have higher well-being
scores (r=.331, p=.049). Motivation and
effort, however, was not signicantly related
to dispositional gratitude and both the affec-
tivity scores.
Figure 1: Change in state gratitude from pre- to post-intervention for the gratitude
group condition versus the control group condition.
Pre- Post-
Estimated marginal means of state gratitude
Intervention periods
Means of gratitude at state levels
.00
2.50
5.00
7.50
10.00
12.50
15.00
Conditions
Control
Gratitude
Health Psychology Update, Volume 26, Issue 1, Spring 2017 15
‘The Three Good Things’ – The effects of gratitude practice on wellbeing: A randomised controlled trial
Table 1: Completer analysis on the effects of gratitude intervention in
the experimental and control group (
N
=81).
Figure 2: Change in positive affect from pre- to post-intervention for the gratitude
group condition versus the control group condition.
Measures Pre-test
mean (SD)
Post-test
mean (SD)
Time Group × time
interactions
GRAT CTRL GRAT CTRL F-ratio p F-ratio p
WEMWBS 46.17
(10.00)
45.69
(9.38)
45.50
(10.81)
39.47
(13.87)
5.110 .027* 3.87 .053
PANAS
PA
31.38
(8.31)
30.87
(7.13)
33.47
(8.23)
28.69
(8.22)
1.987 .163 4.895 .030*
NA 22.00
(9.05)
21.93
(7.65)
20.83
(6.62)
23.38
(8.93)
.147 .703 1.753 .189
GAC 9.83
(3.87)
9.69
(2.75)
11.67
(2.55)
9.13
(3.62)
.416 .521 8.476 .005**
GQ-6 33.44
(5.99)
31.82
(6.18)
33.36
(5.80)
28.16
(8.86)
7.884 .006** 4.184 .044*
Perceived
quality of
relationship
14.39
(4.44)
13.36
(3.15)
13.61
(2.50)
12.78
(3.40)
.496 .483 .871 .354
Physical
symptoms
4.46
(2.98)
5.07
(3.20)
3.77
(3.01)
4.34
(3.11)
5.563 .021* .055 .816
* p < .05;
** p < .01
Intervention periods
Pre- Post-
Conditions
Control
Gratitude
Estimated marginal means of positive affect
Means of positive affect
10.00
.00
20.00
30.00
40.00
50.00
16 Health Psychology Update, Volume 26, Issue 1, Spring 2017
Siew Tim Lai & Ronan E. O’Carroll
Discussion
One approach to boost an individual’s
contentment is the deliberate practice of
counting one’s blessings. To date, grateful
induction to alter one’s dispositional grati-
tude has not been investigated in a system-
atic manner (Emmons, 2007). Future work
can explore whether continuous practice
of gratitude-oriented activities increases a
person’s disposition toward gratitude.
Some may express gratefulness only
under certain circumstances (Watkins,
2004). Through journaling one’s grateful
thoughts, we can determine whether the
immediate feelings of gratefulness can be
cultivated. Our results suggest that keeping
a gratitude journal increases state gratitude;
this is congruent with ndings from previous
studies (Emmons & McCullough, 2003;
Martínez-Martí et al., 2010).
Another main nding emerged from
this study is that participants who practiced
gratitude had more positive affect (PA) and
less negative affect (NA) compared to the
control condition. Gratitude may operate
through savouring – a conscious focus on
one’s fortunate moments that could have
been otherwise (Bryant, 2003). Our gratitude
intervention may have successfully increased
PA through the accessibility and retrieva-
bility of pleasant memories (Watkins, 2004),
contributing to one’s subjective wellbeing.
Consistent with Emmons and McCullough’s
(2003) study, the gratitude intervention
did not lead to signicant reduction in NA.
Nevertheless, the mean scores for NA were
in the expected direction. The attrition rate
(over 30 per cent) may have led to insuf-
cient power to detect signicant differences.
We found that those who keep a grati-
tude journal had relatively stable wellbeing
scores. Fredrickson’s (2001) broaden-and-
build model suggests that gratitude harnesses
behavioural and cognitive repertoires by
‘undoing’ the adverse effects of negative
emotions. Grateful responses to life – as
Fredrickson (2001) claimed, build enduring
coping resources to stabilise mood when
stressful life-events arise. Several studies (e.g.
Tugade & Fredrickson, 2004) support this
interpretation.
Somewhat contrary to our expectations,
gratitude appeared to worsen the perception
of relationship quality. Gratitude prototypi-
cally, stems from the recognition of received
aid is evaluated as costly and altruistic (Wood
et al., 2007). It is possible that the expression
of gratitude causes momentary experiences of
‘indebtedness’ – an obligated feeling to return
the giver the valuable act (Emmons, 2007).
Indebtedness is associated with feelings of
shame and guilt (Emmons, 2007) which may
complicate or reduce the quality of interper-
sonal relationships. Both ‘thankfulness’ and
‘indebtedness’ are embedded in reciprocity,
but the subtle differences in appraising the
benefactor’s intentions (benevolent vs. ambig-
uous) determines the recipient’s emotional
responses (Tsang, 2006). This suggests that
received benets should be considered when
future research examines its interaction with
interpersonal consequences.
Regarding physical wellbeing, there were
no differences between conditions. Though
the main effect of time revealed signicant
changes across conditions, both groups
reported having experienced less physical
symptoms.
The current study sought to examine how
a person’s motivation and effort inuence
the success of the intervention. The ndings
showed participants who put greater motiva-
tion and effort into the gratitude-inducing
activity had increased feelings of grateful-
ness. This is consistent with previous studies
(Sheldon & Lyubomirsky, 2006), which
suggested that when the mood-enhancing
activity ‘ts’ the person’s interest and values
and is performed with appropriate effort,
the goal of developing a grateful thinking is
achievable.
Changes in wellbeing, however, were not
signicantly correlated with effort. Volitional
activities like the gratitude-inducing exercise
require commitment and a certain amount
of effort to initiate, engage, and maintain
Health Psychology Update, Volume 26, Issue 1, Spring 2017 17
‘The Three Good Things’ – The effects of gratitude practice on wellbeing: A randomised controlled trial
the activity (Sin et al., 2009). As Sheldon et
al. (2006) stated, if a person yearns for happi-
ness but does not exert any effort to practice
the mood-enhancing strategy, they may not
experience signicant increase in wellbeing.
While motivation and effort are important
variables for continued adherence to the
activity (Lyubomirsky et al., 2011), only moti-
vation was positively correlated with adher-
ence in this study.
Limitations
First, the randomisation was not entirely
successful as some differences between
groups were evident in pre-intervention.
This was dealt with by including these vari-
ables as covariates in the analyses. Second,
reduction in sample size due to attrition
resulted in reduced power to detect signi-
cant changes; however our ITT results were
very similar. Last but not least, the lack of
longer-term follow-up means that we cannot
comment on the sustainability of interven-
tion effects.
Future directions
Although the current ndings have advanced
our understanding of how gratitude affects
an individual’s wellbeing, many questions
remained unanswered. Pre-existing traits
(e.g. trait gratitude or affective traits) may
affect an individual’s ability to benet from
the gratitude intervention (Emmons, 2007).
Can we expect gratitude induction to work
better in improving health outcomes of
less or more grateful individuals? Further
research is required to explore the trait-
moderator link.
Conclusion
Our results suggest that the count-your-
blessings approach may be an effective tech-
nique to increase individuals’ predisposition
to experience gratitude. A mindfulness
appreciation helps individuals to focus on
benets (Emmons, 2007). Future studies are
required to test the effectiveness of gratitude
interventions against active control condi-
tions and other psychological interventions.
This study shows that a simple count-your-
blessings intervention can improve psycho-
logical wellbeing and could potentially be
included alongside existing psychological
interventions.
The Authors
Siew Tim Lai, and Ronan E. O’Carroll,
University of Stirling, Scotland, UK
Correspondence
Lai Siew Tim
Department of Psychology,
University of Stirling, Stirling,
Email: lai.siewtim@gmail.com
18 Health Psychology Update, Volume 26, Issue 1, Spring 2017
Siew Tim Lai & Ronan E. O’Carroll
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