A non-inferiority randomised controlled trial comparing the clinical and cost-effectiveness of one session treatment (ost) with multi-session cognitive behavioural therapy (cbt) in children with specific phobias.

Project: Research project (funded)Research

Project Details


Background. One-session treatment combines multiple approaches within a single session and has been found to be effective for the treatment of specific phobias in adults. Whether this less resource-intensive treatment can be as effective as CBT in children is of considerable importance in informing health services on best policy and practice.

Aim: To evaluate whether one session treatment can improve clinical and cost effectiveness of treatment of specific phobias in children.

Design: A multicentre pragmatic non-inferiority RCT comparing one session treatment to multi-session CBT, with a 9-month internal pilot. We anticipate recruitment of 13 per month and retention rate of 80% at 6 months follow-up. At 9 months we expect to recruit n= 115 of which one-third will have reached the primary endpoint. Stop/Go criteria based on 75% of recruitment target and 60% of outcome measures will be used to assess feasibility. Allocation to groups will be conducted remotely by Sheffield CTRU. We will ask participants their treatment preferences at baseline. This will not affect group allocation but will allow us to examine the impact of patient preference in the analysis.

Setting: Recruitment through schools, primary care, child mental health and IAPT services in 4 geographical locations.

Target population: Children aged 7-16, with a specific phobia that impacts on their daily functioning as measured by the CAIS-P.

Health Technology assessed: One Session Treatment is a combination of treatment techniques intensified into a single 3-hour session. This method combines graduated exposure therapy, participant modelling, reinforcement, psychoeducation, cognitive challenges, and skills training.

Measurement of outcomes: The primary outcome measure will be patient scores on the Behavioral Approach Test (BAT) conducted by an independent observer blind to allocation, 6 months after trial entry. The primary outcome and secondary outcome measures listed below will be assessed at baseline and 6 months.
1. Clinical severity rating using the ADIS–C (Silverman & Albano, 1996).
2. The Fear Survey Schedule for Children—Revised (FSSC-R; Ollendick, 1983)
3. The EQ-5DY(19). (The EuroQol Group, 1990)
4. Child Anxiety Impact Scale (CAIS-P) (Langley et al, 2004)

Sample size: We need to recruit 154 participants per group (308 in total). This gives 90% power with 5% statistical significance for a range of equivalence of 0.4, assuming attrition of 20% and therapist effects (ICC=0.01). The range of equivalence is based on the meta-analysis conducted by Reynolds (2010).

Data analysis: The statistical analysis will be performed on an ITT basis and reported according to CONSORT guidelines. The primary outcome, the mean BAT score at 6 months, will be compared between groups using an ANCOVA analysis to compare the groups controlling for baseline scores. We will undertake a cost-effectiveness analysis at the end of the trial by comparing the cost of the intervention to any treatment benefit. A long-term analysis to project the impact of the treatments on quality of life over a longer period will also be conducted.

Project timetable: 48 months: study set-up (10 months); school screening (2 months); total recruitment (including a pilot period of 9 months) (24 months); follow-up (6 months), closedown, analysis and write-up (6 months).

Layman's description

A specific phobia is a type of anxiety disorder which causes an overwhelming and unbearable fear and avoidance of whatever is causing the fear, for example, an animal, situation or activity. It estimated that between 5% and 10% of children have a specific phobia which impacts on their everyday lives and lasts for an average of about 20 years. Despite this, fewer than 10% report asking for help for their phobia but do use medical care for other things at a higher rate than most other anxiety disorders. Specific phobias can cause considerable problems at school or college, personal distress, and interference in day-to-day activities.

Cognitive Behaviour Therapy is the most successful treatment for anxiety disorders and phobias however it is expensive in terms of time. Additionally, people need to attend for several sessions which may lead to them not completing all the sessions. As a result, services are moving towards low-intensity treatments with the potential to be implemented across the NHS. A promising alternative, One Session Therapy (OST), has been shown to be successful but has yet to be examined with children. Therefore there is a need to test whether simple phobias severe enough to interfere with daily functioning can be successfully treated using a single session CBT which is less expensive and time-consuming.

To answer this we plan to compare a single session CBT treatment with multi-session CBT. Single session CBT combines graduated exposure to the source of fear, alongside strategies for managing fear and promote coping. It has been shown to be particularly helpful with alleviating specific phobias. Multi-session CBT is a commonly offered treatment which involves both cognitive (e.g. addressing unhelpful patterns of thinking) and behavioural (e.g. exposure) aspects.

The main difficulty of carrying out this comparison will be to recruit a large number of children (aged 7-16) with a specific phobia that impacts their daily lives. We will supplement standard recruitment through referrals to child mental health and IAPT services with more active recruitment techniques through schools and primary care. We will recruit from 4 locations: Leeds, York, Manchester and the North East. To help us get the number of people that we need we will screen children in schools using the fear survey schedule and the Child Anxiety Impact Scale, to ensure that we identify the children most in need of help. To support this recruitment, we plan to recognise and include the frequency and complexity of other illness in children with specific phobias.

Once recruited, children will be randomly allocated to receive either one session or multi-session CBT. We will ask them their treatment preferences which will not affect their allocation but will allow us to examine the impact of patient preference.

The main thing we will test will be to see how close the children can get to whatever it is that they are afraid of, measured on the Behavioural Avoidance Test. This will be assessed before starting treatment and again at 6 months. We will also look at how severe their phobia is clinically, how scared they rate themselves, their quality of life and the impact that their fear has.
Short titleAlleviating Specific Phobias Experienced by Children Trial
Effective start/end date1/07/1630/06/20