The effectiveness of spaced versus massed alcohol avoidance training in inpatient alcohol use disorder treatment: A multisite randomized trial

Alcohol Avoidance Training (AAT), is one of several Cognitive Bias Modification
paradigms that is used to retrain alcohol approach biases (Eberl et al., 2014).
Pictures of alcoholic and non-alcoholic beverages are used as stimulus
material. Participants are instructed to react with a joystick to the tilt of
pictures, presented on a computer screen. For instance, participants make an
approach movement (pull) with left-tilted pictures, and make an avoidance
movement (push) with right-tilted pictures. Pulling increases the size of the
pictures whereas pushing decreases their size. After the correct movement is
made, the pictures disappear, otherwise they do not, until the correct response
is made. It has been demonstrated in lab studies, that a change in approach
bias (increased avoidance of the targeted substance) predicts consumption
behaviour of the targeted substance (Stacy & Wiers, 2010). Therefore, when a
strong training effect can be demonstrated, a clinical effect is likely to
ensue.
Research thus far indeed suggests that AAT provides a clinical
effective add-on to TAU in the treatment of Alcohol Use Disorder (AUD). The
first study on the effectiveness of AAT in problematic alcohol use was
conducted in a non-clinical sample of 42 male students, classified as hazardous
drinkers (Wiers, Rinck, Kordts, Houben, & Strack, 2010). The results showed
that the automatic action tendencies to approach alcohol were reduced. In 2010,
the first Randomized Controlled Trial (RCT) using AAT in patients with AUD was
conducted. The sample consisted of 214 inpatients. When AAT was added to TAU,
the total number of relapses after one year decreased by about 10% compared
with patients who had received a sham or no training (Wiers, Eberl, Rinck,
Beckers, & Lindenmeyer, 2011). Importantly, the clinical effect was replicated.
In addition, analyses revealed four to six AAT sessions to be the mean optimum
number of sessions needed (Eberl et al., 2013; Manning et al., 2016). Although
the effect sizes found are small to medium (Kakoschke, Kemps & Tiggeman, 2017),
the results are interesting given the high relapse rates (Brandon, Vidrine, &
Litvin, 2007) in addiction treatment and minor burden related to the
intervention.
Apart from the replicated clinical effectiveness, in our own clinical
experience, AAT can be easily integrated with (inpatient) TAU. It does not
require highly trained therapists as is the case in Cognitive Behavioral
Therapy (CBT) or Community Reinforcement Approach (CRA). In addition, four to
six AAT sessions will take the participant an average of 60 to 90 minutes total
to complete. Therefore, the burden in time is low which may increase engagement
and attendance and decrease drop-out. Finally, AAT can be provided as early as
during detoxification (Manning, Mroz, Garfield, Staiger, Hall, Lubman, &
Verdejo-Garcia, 2019; Manning et al., 2016) and may even be more effective than
when provided after detoxification. In comparison, traditional CBT and CRA
interventions are thought to be less effective during detoxification as a
result of dampened cognitive functioning in attention and often executive
functioning as a result of prolonged abuse (Aharonovich, Shmulewitz, Wall,
Grant, & Hasin, 2017; Domínguez-Salas, Díaz-Batanero, Lozano-Rojas, &
Verdejo-García, 2016).
AAT is already recommended in German clinical treatment guidelines and may be
incorporated in the next revision of the Dutch clinical guidelines on AUD (the
current, outdated version is of 2009). Therefore, AAT has been implemented as
part of routine clinical care for AUD treatment in inpatient settings of
*IrisZorg* (a Dutch addiction care provider).

Although the optimum length of alcohol avoidance training has been studied,
little is known about the impact of the distribution of these sessions over
time. As a result no guidelines or recommendations exist on whether AAT
sessions should be spaced out over time or provided in a massed format.
In clinical practice (within our inpatient care facilities), AAT as standard
treatment is commonly administered during the first week after detoxification.
Although, in semantic learning, *cramming* of learning episodes within a short
period of time (known as *massed practice*) has been found to be effective for
short term retention. When long term retention is preferable, learning episodes
should be spaced out over longer periods of time (Cepeda, Rohrer, Wixted &
Pashler, 2008). Optimum criterion performance is achieved when lag between
sessions is approximately 10-20% of the desired retention interval.
Spacing effects have been demonstrated on numerous explicit measures of
memory (Donovan & Radosevich, 1999; Janiszewski, Noel & Sawyer, 2006; Cepeda,
Rohrer, Wixted & Pashler, 2006) and sometimes implicit learning (Greene, 1990;
Jacoby & Dallas, 1981). Greene (1990) added that spacing effects in implicit
leaning are eliminated by incidental learning, thus disproving that the spacing
effects apply to all forms of learning. To our knowledge, the impact of spaced
learning on the procedural learning that is involved in AAT has never been
evaluated in a controlled study. It is not self-evident that distributed
practice will be more effective than massed practice. AAT research has thus far
shown that even small effect sizes can accumulate to substantial changes in
clinical effects. Knowledge about the optimum distribution of AAT session are
of importance for the ongoing development of AAT.
This study will be used to evaluate the possible superior effect of spaced
practice AAT in multiple inpatient addiction care facilities. Effectiveness
will refer to the possible impact of spaced practice
(AAT-S) compared to the massed practice control group (AAT-M) on clinical
outcomes in terms of alcohol consumption and craving.
*

See fig. 1, pag. 15 of the study protocol

The study is a RCT with two arms, with a baseline, three and six month follow
up assessment, to evaluate the effects of spaced vs massed AAT sessions as part
of inpatient, routine clinical care for patients with AUD (see Fig. 1.). For
the primary objective (to determine superiority of spaced practice AAT over
massed AAT), a sample size of N = 200 will be required (see section 4.4).
The recruitment phase of the study runs from november 2021 (projection) until
december 2022 (or earlier, when the intended sample size is reached), while the
data-collection phase (including the six month follow-up period) may commence
until september 2023.

Participant receive either AAT-M of AAT-S within a broader context of routine
clinical care. AAT-M is an element of current routine care. The only difference
in the AAT-S condition is that the AAT sessions are spread out over four weeks.
After baseline assessment, AAT-M participants will receive 4 AAT sessions (each
with 300 trials) within the space of 8 days (which totals 1200 trails). AAT-S
participants will also receive 4 AAT sessions totalling 1200 trails but spaced
out over four weeks (one AAT session per week).

Participants receive routine clinical care. Additionally, one short
questionnaire will be provided pre-AAT. Since all participant will be provided
the same amount of AAT trails, albeit in different intervals, no adverse
effects are to be expected. Three and six months after treatment participants
will be provided with a follow up questionaire (same as pre-AAT) via
telephone.