Web-based intervention based on Acceptance & Commitment Therapy (ACT) and mindfulness for chronic pain patients: A randomized controlled trial

Chronic pain is highly prevalent in Western countries. Cognitive and behavioral
therapies for the treatment of chronic pain have been established, but new
factors useful for the treatment of pain have been acknowledged. One of these
factors is acceptance. Different laboratory and clinical outcome studies
suggested acceptance strategies to be important in restoring functioning and
quality of life in the presence of chronic pain. Examples of preventive
mechanisms and treatments based on acceptance are Acceptance & Commitment
Therapy (ACT) and mindfulness. The University of Twente has developed several
effective interventions based on ACT and mindfulness for adults with
psychological problems. Now a web-based intervention based on ACT and
mindfulness for chronic pain patients has been developed, called *Leven met
Pijn online*. The goal of this study is to evaluate the effectiveness of *Leven
met Pijn online* in a randomized controlled trial.

The primary objective of this study is to evaluate the web-based intervention
*Leven met Pijn online* for chronic pain patients in terms of a decrease of
interference in daily life due to pain. The secondary objective of this study
is to evaluate *Leven met Pijn online* in terms of a decrease in pain
disability and pain intensity, and an increase in mental health, satisfaction
with life, psychological flexibility, mindfulness and values-based living.
Another objective of the study is to evaluate the mediating effects of
psychological inflexibility and mindfulness in the effects described in the
primary objective.

A randomized controlled trial will be carried out with three parallel groups:
1) Experimental condition: Web-based intervention *Leven met Pijn online*.
Participants are involved from entry/intake until the last measurement for 14
months. There are six measurement points.
2) Minimal intervention condition: Web-based intervention *Expressive writing*.
Participants are involved from entry/intake until the last measurement for 14
months. There are six measurement points.
3) Waiting list control condition: Participants will be on a waiting list for
six months after randomisation (eight months after entry). They receive an
online course of their personal choice after the first follow-up measurement,
three months after the end of the intervention for the experimental condition
(eight months after entry). Participants are involved in the study for 11
months. There are five measurement points.

As all participants will be randomly assigned to the three groups at one
specific moment, there is a waiting time with a maximum of six weeks before
people know in what intervention group they are enrolled.

The intervention is based on the self-help book *Leven met Pijn* and the
web-based intervention *Voluit Leven online* for adults with psychological
problems. The intervention is based on ACT and mindfulness. There are 9
modules, which can be worked through in 9-12 weeks. Patients receive exercises
on acceptance and mindfulness and explore how they can apply their personal
values in daily life. Feedback from a counsellor will be received by e-mail
contact on a weekly basis.

No risks are expected from participation. Participants can choose for
themselves to sign up for study participation. The burden with regard to time
and mental effort are not expected to be too high. Participants are enrolled in
the study for 11 or 14 months. There is a waiting time with a maximum duration
of six weeks between entry in the study and randomisation over the three
groups. If burden of participation is too high, participants can always decide
to stop and drop out of the study. Also the questionnaire assessment does not
seem to be a very high burden (45 - 60 minutes at T0, T3, T4 and T5; 20 minutes
at T1 and T2). If it appears from intake that participants have severe
psychiatric problems, they will be advised strictly to see a GP as soon as
possible. Participation probably will have benefits such as a decrease in pain
interference, pain disability and an increase in mental health, psychological
flexibility, mindfulness and values-based living.