Economic Protocol for Mental Health Intervention

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Merit

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Mindfulness-based therapy for people with schizophrenia: randomised control trial and

economic evaluation protocol.

Introduction

Schizophrenia is a neuropsychiatric disorder characterised by the presence of

psychopathological domains, such as delusions, hallucinations, formal thought disorder,

motor abnormalities and negative symptoms (1).

Although this disorder is not particularly frequent, with an estimated prevalence around 1%

(2), it is one of the most disabling conditions according to the Global Burden of Disease

studies (3, 4).

People with schizophrenia not only suffer from symptoms, but also from the consequences of

stigma, neglect and abuse (5, 6). Indeed, people with schizophrenia are less likely to be

employed (7) or have their own house (8), and they die 15–20 years earlier than the general

population (9).

In addition, schizophrenia represents a costly condition for patients, caregivers and the

society. For instance, cost-of-illness systematic reviews have calculated prevalence-based

annual costs for schizophrenia ranging from US$94 million to US$102 billion (2013 US

dollars) (10-12).

Pharmacological treatment is one of the cornerstone of schizophrenia therapeutics (13),

however, noncompliance is a challenging issue (14) and even with adequate adherence, up to

30% of patients experience partial response (15). Psychosocial interventions have been

developed in order to increment treatment compliance, but also to help people to cope with

their symptoms, reduce relapses and increment social functioning (16).

The specific case of cognitive behavioural therapy (CBT) has received special attention in the

literature, being recommended even in patients who are resistant to pharmacological

treatment (17). In addition, some economic evaluations have demonstrated that CBT is a

cost-effective intervention from a health perspective (18-20).

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Mindfulness-based therapy (MBT), by contrast, has only recently started to be used to treat

people with psychosis (21). This is an operationalised intervention that includes the

development of cognitive and affect dimensions to embrace internal experiences, rather than

avoid them (22). This intervention includes guided meditation and can be added to cognitive

therapy (23).

Despite initial concerns about the use of meditation in schizophrenia, pilot studies have

demonstrated the feasibility of using MBT for psychosis (24) and clinical trials have shown

that it can alleviate the distress associated with hallucinations and paranoia (25). Two recent

meta-analyses have evaluated the clinical effectiveness of mindfulness-based therapy for

psychosis (26, 27) with favourable results in terms of symptomatology and rehospitalisation

rate.

With this evidence, some people have argued that MBT should be included in the clinical

guidelines, as well as CBT (23). However, until the moment of writing this protocol, no

economic evaluation has been done to probe the cost-effectiveness of such intervention.

Hence, a new randomised trial with an economic evaluation is needed to assess whether MBT

for psychosis represent a valuable therapeutic choice.

Policy question and perspective

This research will answer the policy question about whether it is worthwhile to include MBT

in the package of care of people with schizophrenia.

To make this decision the health service perspective is crucial. Since this protocol is intended

to be applied to the UK setting, the NHS and Personal Social Services perspectives will be

considered according to the NICE recommendations (28).

However, schizophrenia has been proven to impact on many areas of people’s lives (7) and

the evidence has shown that most of costs are indirect costs (11). Hence, a broader

perspective seems more appropriate.

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In addition, this research could also be relevant to other policy groups interested in the care of

people with schizophrenia, such as non-governmental organisations (NGO), family and

service-user organisations and research agencies.

Therefore, a societal perspective will be taken, including costs related to health and social

care, but also to productivity losses and costs of informal care.

Productivity losses will be included given that people with schizophrenia have a diminished

ability to work. This is partly due to the symptomatology (cognitive and negative symptoms

(1), but also due to the fact that the first episode of psychosis usually occurs in early

adulthood with a chronic course (29).

Although informal care is not mandatory by NICE, there is substantial evidence on the

impact of schizophrenia in family and caregivers (30) and many of such burden could

eventually implies costs for the NHS, because higher proportion of depression and physical

complaints (31).

Aim

The aim of this study is to assess the clinical and economic value of adding a mindfulness-

based intervention (MBT) to CBT for people with schizophrenia from a societal perspective.

Objectives

1) To compare effectiveness of CBT plus a MBT intervention versus CBT alone on

short- and long-term clinical outcomes in people with schizophrenia from secondary

care settings.

2) To evaluate the cost-effectiveness and cost-utility of adding MBT to CBT for people

with schizophrenia from secondary care settings.

Hypothesis

The addition of MBT to CBT is associated with less symptomatology amongst people with

schizophrenia compared with CBT alone.

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CBT with a MBT intervention results in a more cost-effective intervention compared with

CBT alone, for the UK context.

Research methods

Research design

A two-arm, parallel, randomised, controlled trial of MBT plus CBT in comparison with CBT

alone.

Setting

Participants will be recruited from secondary care facilities, either inpatient or community

mental health teams. Specialised services, such as early intervention in psychosis services or

assertive teams will be also included.

Eligibility criteria

Patients aged 18 to 64 years with a diagnosis of schizophrenia-spectrum psychosis according

to the DSM-5 or ICD-11 criteria. This includes schizophrenia, schizophreniform disorder,

delusional disorder and schizoaffective disorder.

Exclusion criteria:

1. Unwillingness to provide informed consent.

2. Intellectual disability defined as an IQ<80.

3. Active comorbidity with substance misuse without treatment.

4. Decompensated physical comorbidity that difficult the interventions.

5. Refusal to psychological therapies.

Intervention

The experimental group will receive MBT according to the procedures developed by Segal et

al (32) and adapted to people with psychosis by Chadwick (24). The rationale for this is its

operationalisation and evidence in previous studies (25, 33). Patients will receive mindfulness

sessions twice a week over a period of 12 weeks led by a trained therapist and will be

encouraged to maintain CD-guided meditation practices at home.

This group will maintain treatment according to NICE guidelines (34), including

pharmacotherapy, social support and CBT.

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Comparator

Patients from the parallel arm will receive treatment according to NICE clinical guidelines

(34) as in the intervention group, but without the mindfulness-based module.

The CBT intervention will be defined as 16 one-to-one based sessions, following a treatment

manual to evaluate links between thoughts, feelings and behaviours (34).

Treatment fidelity

The therapists in the experimental group will complete a form after every session, which will

be assessed by a research team member for treatment fidelity. CBT sessions will be recorded

(in both arms) and will be stochastically evaluated.

Outcomes

The primary outcome will be the change in the Clinical Global Impression-Schizophrenia

(CGI-SCH) (35). The rationale for this is that psychological therapies for schizophrenia have

a focus on how people deal with distressing symptoms, instead of only reducing them (36).

The CGI-SCH scale is applicable by clinicians and it permits evaluate the severity and

general functioning. Psychometric evaluations have demonstrated high reliability and high

correlation with other scales such as GAF and PANSS (35).

The main secondary outcome will be the quality-adjusted life years (QALY). For this study,

the SF-6D instrument will be used. This is an instrument developed by Brazier from the SF-

36 (37). The SF-6D has demonstrated advantages over the EQ-5D specifically in people with

schizophrenia, such as to reflect better the severe nature of the condition, being more

sensitive to change, has a normal distribution and lack of ceiling effect (38).

Other measures

The PANSS (39) will be applied to evaluate more specifically the symptomatology of

schizophrenia and its correlation with CSI-SCH. The Social functioning scale (40) will

evaluate general aspects of recovery.

At baseline, sociodemographic characteristics of participants will be recorded joint with costs

and outcomes measurements. Next assessments with costs evaluation (see forehead) will be

at 3 months (just after the intervention), 6 months and 1 year.

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Study procedures

Recruitment and preparation

Patients will be recruited from secondary care facilities from a defined catchment area of

London. Evaluators will be trained in measurement instruments. Inter-rater reliability will be

assessed with practice interviews.

Allocation

Treatment allocation will be generated by an independent computer-derived random sequence

for purposes of concealment. An administrator will inform to patients, key health-workers

and MBT therapists of the allocation by phone.

Blinding

The principal investigator and assessors will be blind to the randomisation status of patients.

This will be maintained by providing instructions to patients, their therapists, clinical teams

and caregivers of no revealing randomisation status. In addition, data will be treated with a

unique identification code to storage and management of the electronic database.

Sample size

The sample size calculations are based on the clinical effectiveness hypothesis.

To detect a mean difference in CGI-SCH of 4 points (which has described as clinically

significant (35)) with a standard deviation (SD) of 4, a two-sided significance level (α) of 5%

and power (1 – β) of 80% would require 17 patients in each arm. However, given the group

modality of the MBT intervention, a cluster effect is likely to be found (41). A new sample

calculation with same means, SD, power and level of significance, but using an intraclass-

correlation of 0.5 and an estimated cluster size of 8 would require 80 participants per arm.

Both analyses were carried out with STATA 14.2, with commands power and clustersampsi

to sample sizes with and without clustering, respectively.

Estimating a conservative drop-out rate of 30%, is planned to be enrol 104 people in each

arm.

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Economic evaluation

Methods

The design for the economic evaluation of the primary outcome will be a cost-effectiveness

analysis. Differences in costs and CGI-SCH scores in both arms will be used to calculate an

incremental cost-effective ratio (ICER) using the following formula (42):

Fig 1. ICER formula for CEA

Where CMBT is the mean costs in the MBT group; CCBT is the mean costs in the control group;

CGIMBT is the mean CGI score in the treatment arm; and CGICBT is the mean CGI score in the

control.

Uncertainty of the ICERs will be simulated by resampling bootstrapping method with 2000

iterations and simulated means for costs and outcomes will be plotted in the cost-

effectiveness plane.

The same process will be applied to the QALYs from the SF-6D, resulting in a cost-utility

analysis of the effect of MBT. This will permit to inform directly to the decision maker with a

generic measure of health gain (42).

Cost-effectiveness acceptability curves will be provided to estimate the probability that the

adding MBT is cost-effective compared with CBT alone (43). The rationale for this are: 1)

Adding a new intervention is likely to be in the northeast quadrant of the cost-effectiveness

plane; 2) There will be uncertainty in the measurement of costs and outcomes; 3) Is unlikely

to find a statistically significant difference between mean costs, given the sample size

calculated (44).

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Cost analysis

Identification

In relation to the perspective of the economic evaluation previously mentioned, relevant

resources will be listed for the health system, formal social care, informal social care and

productivity losses.

Direct medical costs will include psychiatric hospitalisation, emergency visits, day-hospital

care, community mental healthcare, medication and general physical care. Hospital- and

community-based staff costs will include those from psychiatrists, GP, nurses and therapists.

Costs of the MBT intervention will be calculated following the people allocated approach

(45). The rationale for this is that groups will be closed at 8 people and every session will run

unless no-one attend. The ratio of direct and indirect time will be extrapolated from a study of

MBT for depression (46).

Costs of formal social care will include supported accommodation and costs of social worker

per hour of contact with patients. Costs of informal care will be calculated based on the

monetary valuation of the time invested by caregivers in assisting the patients (47).

Measurement

According to recommendations of a taxonomy for resource use measurement (RUM) (48),

this study will calculate resource use in the following way: 1) Source of data: patients and

patient proxies (caregiver or relative); 2) The RUM will be completed by a member of the

research team; 3) It will be administrated in a face-to-face basis; and 4) recorded in an

electronic format following a pre-stabled questionnaire.

The healthcare utilisation will be measured through the Client Socio-demographic and

Service Receipt Inventory (49), which is a recall questionnaire that allow measurement of

health and social care utilisation, specially validated for mental health and with independently

assessment of correlation with computerised records (50). Informal care will be measured by

a face-to-face questionnaire (51) and the productivity losses will be calculated by the World

Health Organization Health and Work Performance Questionnaire (HPQ), a self-report

instrument which estimate the workplace costs of health problems (52).

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Valuation

The valuation of health and social care resources will base on published PSSRU unit costs of

Health and Social Care 2016 (53).

To value the informal care provided by caregivers, because the high burden of people caring

schizophrenic patients (54), the wellbeing method shall be used (55).

Finally, the friction cost approach (56) will be used to value the productivity losses, given the

evidence that overestimation by the human capital approach in schizophrenia (57).

Statistical analysis

Analysis will be carried-out with an intention-to-treat basis. This means that data will be

analysed according to initially allocated group, independently of withdrawals (58). Missing

data will treated through the multiple imputation method if they miss at random basis (59). If

such assumption is not satisfied, adjustment and modelling mechanisms will be explored

(60).

To examine successful randomisation, chi-squared and t-test statistics will be used. Baseline

characteristic with the results of statistical test will be presented in tables with 95%

confidence intervals and p-values less than 0.05 will consider significant.

Differences in the mean score of the outcomes and costs will be compared using the t-test

with adjustment by baseline characteristics and costs values.

As a result of the previously mentioned clustering effect, a multilevel analysis will be carried-

out to take into account the differences in therapists’ performance (41).

Several sensitivity analyses will be carried-out to test assumptions in measurements of costs

and outcomes, as well as for loss of follow-up and missing data.

Presentation of the results

Comparison between costs and outcomes will be presented in the form of ICERs (with

resampled estimations) in a cost-effectiveness plane. Cost-effectiveness acceptability curves

with willingness to pay (WTP) ranging between £0 and £35,000 per QALY will permit to the

policy maker take a decision based on the probability of that MBT be cost-effective.

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Ethics arrangements and dissemination

Research Ethics Committee approval will be obtained before the start of the project.

All eligible participant will require a written consent to be included in the trial, which will be

conducted according to the Declaration of Helsinki (61).

The results of this research will be published in peer-review journals, anonymised data will

be accessible for sharing for non-commercial aims and it hopes improve the care of people

with schizophrenia.

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