An investigation into the treatment of chronic low back pain

Exposure in vivo therapy (EXP) aims to reduce pain-related fear - a key
maintaining factor of chronic low back pain (CLBP) - while increasing level of
daily functioning, despite the pain. This is done by exposing patients to their
most feared activities/movements, while behavioural experiments are performed
that serve to correct catastrophic (erroneous) beliefs about pain. Yet,
performing exposure exercises might be very threatening for patients and might
encourage them to build in subtle safety behaviour (SB) during EXP. Whether SB
should be allowed or not during therapy is heavily debated. Whereas some argue
that it will only interfere with therapeutic progress because it prevents the
disconfirming experience EXP tries to offer, others argue that it will
facilitate therapeutic progress, because it enhances one's sense of control, if
used judiciously. So far (clinical-)experimental studies have provided mixed
evidence nor have they lead to any clinical recommendation.

The main aim of the current study is to investigate the influence of these SBs
on therapeutic progress and outcome. We hypothesize that: 1) SB has a
facilitating effect on fear reduction within a therapy session, but that it is
also related to stronger fear increase in between sessions and in the long run
compared to when SB is omitted from therapy, 2) patients using SB during
therapy might benefit less in the long run compared to when SB is omitted from
therapy.

A secondary aim of this study is to gain more insight into the concept of SB,
since there is a lot of confusion with regard to what SB is.
Specifically, we aim to
- Further identify which SB*s are commonly used (active, passive, overt and
covert) in CLBP patients
- Monitor the spontaneous use of SB during daily functioning
- Find out to what extent SB is related to level of pain-related fear and level
of functional disability

The study entails a replicated single-case experimental design in 12 patients
with chronic low back pain. Participants are randomly assigned to one of three
groups: 1) an Exposure-neutral group (SB-neu), 2) a group receiving EXP with a
SB maintenance instruction (SB-main) 3) a group receiving EXP with a SB
decrease instruction (SB-decr).

The study entails a replicated single-case experimental design in 12 patients
with chronic low back pain. Participants are randomly assigned to one of three
groups: 1) an Exposure-neutral group (SB-neu), 2) a group receiving EXP with a
SB maintenance instruction (SB-main) 3) a group receiving EXP with a SB
decrease instruction (SB-decr). The usual treatment course is followed, but
some additional sessions are scheduled for the study. The study consists of 25
sessions spread over 16 weeks plus 3 more sessions during follow-up (total
number of 28 sessions). Note that the number of weeks or sessions may vary
depending on scheduling issues or depending on the progress of the patient.

Phase 1: Preparation (week 1 - week 3)
1. Intake session with the (rehabilitation) physician
a. Patients are medically evaluated by the (rehabilitation) physician to
exclude any serious medical pathology and make sure the patient is suited for
entering in an exposure program (regular care).
b. The patient (and the spouse/partner) are informed about the possibility to
participate in a study (additional).
c. If the patient is willing to participate, written consent to have the
researcher contact the patient by telephone is obtained (see section E1.A,
E2.A). Then, the patient (and partner) receive(s) patient and partner
information as well as the *Algemene brochure medisch-wetenschappelijk
onderzoek* (additional).
2. Contact by telephone by the researcher: when written consent to be contacted
is obtained, this information is passed on to the researcher, who then contacts
the patient by telephone to explain what study participation entails and
address questions the patient or the partner may have.
3. Screening sessions (regular care)
a. The patient is screened by a behaviour therapist, a physical therapist and
an occupational therapist.
The behavioural therapist checks for psycho-social counter-indications and
explores the history of the complaints. This helps to identify the best
treatment options for a specific patient The physical therapist check for any
physical counter-indications; the occupational therapists explores the
patients* motivation, expectation and personal goals.
4. Information & screening session with the researcher (additional)
a. The researcher explains the study, answers all questions related to study
participation, and explains the use of the daily measures (additional).
b. Written informed consent for study participation is obtained with the
patient and partner (see section E1.B, E1.C, E2.B., E2.C).
c. All of the inclusion and exclusion criteria are checked.
5. A cognitive-behavioural analysis of the patients* complaints is made by the
therapist (team; psychologist and physical or occupational therapist) and based
on this, treatment goals are formulated (regular care).
a. Daily measures are started from here on until 1-week post treatment
(additional).
6. PHODA-session
a. A hierarchy of feared activities is set up with the Photograph Series of
Daily Activities (PHODA). Based on the fear hierarchy, the exposure exercises
are selected (regular care).
b. The SB*s that are used during those activities are identified. Because
patients themselves are not always aware of the SB*s they are using, the
partner is also asked to join in on the identification of SBs (additional).
c. A Safety Behavior Quesionnaire is administered to the patient and the
partner (additional).
7. Explain treatment recommendation: the rehabilitation physician discusses the
treatment recommendation of the therapist (team) with the patient (regular
care).
Phase 2: Baseline 1 (week 4 - week 5)
8. Measurement occassion 1 (M1; additional)
a. This entails a baseline period in which no treatment sessions are planned of
7 to 14 days before of the first therapy session, thus creating a
pseudo-randomization. Daily measures are further completed by the patient and
the partner.
b. The patient visits the azM to fill out the battery of questionnaires.
c. During this visit, the patients performs a standard behavioural performance
task, as well as a personalized behavioural task.
d. The presence of the partner is also requested during this measurement.
Phase 3: Education (week 6)
9. Education session by therapist (team):
a. This involves an explanation of the FA-model (regular care)
b. Additionally, the SB-neu group receives a treatment rationale that makes no
explicit reference to the use of SB, while the SB-main group receives the
rationale that SB may be used to make matters easier, and the SB-decr is told
that SB is best omitted in order to reach the desired outcome (additional).
10. Education session by the rehabilitation physician: the rehabilitation
physician explain the medical results that have been obtained with the patient
(e.g., discussing X-rays, MRI imaging)
Phase 4: Baseline 2 (week 7 - week 8)
11. Measurement occasion 2 (M2; additional)
a. Daily measures are further completed by the patient and the partner.
b. The patient visits the azM to fill out the battery of questionnaires.
c. During this visit, the patients also performs a standard behavioural
performance task, as well as a personalized behavioural task.
d. The presence of the partner is also requested during this measurement.
Phase 5: Exposure in vivo (week 9 - week 15)
12. Exposure in vivo sessions (about 12 sessions on average, 2 sessions/week).
The therapist (team) proceeds with sessions consisting of exposure exercises
and behavioural experiments. During these sessions and depending on the
condition, the previously explained treatment rationales are explained again:
no explicit reference to SB (SB-neu), SB-maintenance instruction (SB-main) or
SB-decrease instruction (SB-decr) (regular care with adjustments per
condition).
13. Measurement occasion 3, halfway during treatment, i.e., after 6 exposure
sessions (on average) (M3; additional).
14. Measurement occasion 4, 1 week post-end of treatment (M4; additional).
(week 16)
Phase 6: Follow up (week 20 - week 56)
15. Measurement occasion 5: 3 months after end of treatment (M5; regular care).
16. Measurement occasion 6: 6 months after end of treatment (M6; additional) .
17. Measurement occasion 7: 12 months after end of treatment (M7; additional)

The current study does not expose patients to any risks that are not usually
related to rehabilitation or movement in general. Patients are requested to
spend some extra time on top of regular care for the purpose of the study. The
extra burden includes:
- filling out daily computerized measures at home starting from 1 week before
M1 until M4, as well as during 10 days at M5, M6 and M7 (about 10min/day for
the patient).
- fill out questionnaires at the azM at 7 different measurement occasions (on
average 30 minutes per measurement occasion).
- perform two behavioural performance tasks at the azM at 7 different
measurement occasions (on average 1 hour per measurement occasion).
- involvement of the partner: help in identification of SB during the PHODA
session and on M1 to M7;filling out daily computerized measures at home
starting from 1 week before M1 until M4, as well as during 10 days at M5, M6
and M7 (about 5min/day for the partner).
Patients are reimbursed for transportation that is required for the information
& screening sessions with the researcher and the 7 measurement sessions (¤ 0,19
per km/car and complete reimbursement for public transportation costs).
Partners are reimbursed for transportation as well, if this requires an extra
transportation besides the one the patient has to make anyway.
Participants will also receive a gift in the form of a breakfast coupon for 2
(¤ 24,90) in return for their study participation.
Indirectly, the participant can help to gain more insight in factors that can
hamper or facilitate therapeutic progress/outcome, and help to formulate
treatment recommendations that may further improve EXP for CLBP in general.