Money for Medication: A randomized controlled study on the effectiveness of financial incentives to improve medication adherence in patients with a psychotic disorder and comorbid substance abuse.

Money for Medication (M4M) is a randomized controlled study on the
effectiveness of contingency management in improving adherence with
antipsychotic depot medication in patients with psychotic disorders and
co-morbid substance abuse. Non-adherence with antipsychotic medication is a
frequently occurring problem, particularly among patients with psychotic
disorders and co-morbid substance abuse (often called *dually diagnosed
patients*). Non-adherence reduces the effectiveness of the treatment of a
chronic psychotic disorder and interferes with therapeutic efforts. Failure to
take the prescribed medication is strongly associated with a wide array of
adverse consequences for both the individual and the community. As
non-adherence to antipsychotic medication is one of the most preventable causes
of relapse and admission, interventions that effectively improve adherence are
needed.

Prior research has shown encouraging results for interventions based on
*Contingency Management* (CM), where desirable behavior is encouraged by
providing rewards contingent upon the behavior. However, little research has
been done on the effectiveness of CM on medication adherence in patients with
psychotic disorders and co-morbid substance abuse. An earlier pilot-study by
our group showed promising results in reducing admission days and increasing
adherence. The current study is a randomized controlled trial to assess the
effectiveness of M4M in improving adherence with antipsychotic medications in
dually diagnosed patients.

Patients will be randomly assigned to the experimental group (M4M, n = 84)
receiving M4M plus treatment as usual (TAU), or to the control group (n = 84)
receiving TAU only. The duration of the intervention is twelve months, after
which a six months follow-up will take place in which the effects of
discontinuing M4M on medication acceptance will be monitored.

Our primary outcome measure will be the percentage of accepted depots during
and after stopping the intervention. Our secondary outcome measures include the
longest period of uninterrupted depot acceptance, the time expired before the
depot is taken, the number of admissions in psychiatric hospitals, patients*
substance abuse, symptoms and social and psychological functioning and
subjective wellbeing. We will also assess cost-effectiveness. In addition, we
will explore patient*s experiences with M4M through assessing their perceived
control over their health and treatment, their attitudes towards medication and
M4M and their treatment. Finally we will assess the clinicians* attitude
towards M4M.

The primary goal of this study is to assess how M4M affects acceptance of
antipsychotic depot medication, during the intervention and after terminating
the intervention.

The current study is a randomized controlled trial. Patients will be randomly
assigned to the experimental condition (M4M) or the treatment as usual (TAU)
control condition. Patients assigned to the experimental condition (M4M) will
receive a financial incentive for each time they accept their prescribed depot,
in addition to treatment as usual.

The proposed intervention is money for medication. Money for medication is
based on Contingency Management (CM) principles. The essence of CM-based
interventions is that a pre-set desirable behaviour is reinforced. In M4M,
patients who accept their prescribed antipsychotic depot medication will
receive a financial incentive directly upon acceptance.

Patients assigned to the intervention group (M4M) will receive treatment as
usual, plus a financial incentive for each time they accept their prescribed
depot of antipsychotic medication. All patients in the intervention group (M4M)
will receive an average maximum of 30 euro per month. The amount of money they
will receive is dependent upon the frequency of the depot. For example, a
patient who receives a two-weekly depot will receive 15 euro per accepted
depot. A patient who receives a three-weekly depot will receive 22.50 euro for
each accepted depot etcetera. The money will be given by the clinician directly
upon administration of the depot injection. Patients will sign a proof of
receipt.

The intervention will take 12 months. After the intervention period, there will
be a follow-up period of 6 months in which the patients receive no financial
incentives for accepting their prescribed antipsychotic depot medication.

All patients will receive treatment as usual. Patients assigned to the control
group will receive treatment as usual only (including the regular encouragement
to take their prescribed depot medication). Treatment as usual includes case
management, sometimes receiving psychosocial interventions, use of crises
services, admission to hospitals and prescribing medication.

The type and dosage of the depot antipsychotic medication and other medications
patients receive will be determined by the patients* clinician. The type,
frequency and dosage will not be affected by participation in the study.
Administration of the depots will be done by the patients* clinicians at the
regular times and locations.

Patients will receive three assessements at month 0 (baseline), 12 (end of
intervention) and 18 months (follow-up). The assessments will take a maximum of
90 minutes. During the assessments, patients will also be asked to provide a
urine-sample. All participants will receive 20 euro per assessment (including
urine-sample).

We expect no serious harmful effects of the current intervention. However, if
M4M successfully increases medication adherence, patients could experience more
side effects of the prescribed medication. This will be monitored by patients
clinician and by asking patients about their subjective wellbeing under
neuroleptics (SWN, de Haan et al., 2002). Another potential adverse event would
be that patients could spent their money on drugs and/or alcohol. We
deliberately kept the amount of money restricted in considering this risk.
Furthermore, we will monitor patients drug use through urine analysis and
assessments (ASI, Hendriks et al., 1989). When this protocol is considered by
the METiGG, we would like to attend the meeting to consider issues more in
depth and to consult the members of the METiGG about how to handle these
considerations best.