Can a brief accessible CBT programme in schools improve the mental health of 16–18-year-olds? Clinical and cost-effectiveness of a cluster randomised controlled trial in Brief Educational Workshops in Secondary Schools Trial (BESST)

June Brown, Sarah Byford, Kirsty James, Ben Carter, James Shearer, Steve Lisk, Crispin Day, Irene Sclare, Paul Stallard, J Deighton, David Saunders, Jynna Yarrum, Peter Fonagy, Tim Weaver, Claire Evans

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Depression and anxiety are increasingly prevalent in adolescents. BESST investigated the effectiveness of a brief accessible stress workshop programme for 16–18-year-olds.

An England-wide multi-centre cluster randomised controlled single-blinded trial to evaluate clinical-effectiveness and cost-effectiveness of a brief CBT workshop (DISCOVER) compared to treatment-as-usual (TAU)(1:1). We planned to enrol 60 schools and 900 adolescents, using a self-referral system to recruit participants. The primary outcome was depression symptoms (MFQ) at 6-month follow-up. Cost-effectiveness, taking a National Health Service (NHS) and personal social services perspective was explored using quality adjusted life years (QALYs). The ISRCTN registration was 90912799.

Between 4th October 2021 and 10th November 2022, 900 adolescents at 57 schools were enrolled, before randomisation of schools. The DISCOVER arm included 443 participants (295 female (67%)) and TAU included 457(346 female (76%)). The ITT analysis included 415 and 439 adolescents (DISCOVER: TAU). The primary analysis found an adjusted mean difference in MFQ of -2.06 (Cohen’s effect=-0·17; 95% CI –0.27 to -0.06; p=0·0019), indicating a clinical effect in the DISCOVER arm. With an incremental cost-effectiveness ratio (ICER) of £15,387 per QALY, the probability of DISCOVER being cost-effective compared to TAU at £20,000-£30,000 per QALY threshold ranged from 61% to 78%. In a pre-specified subgroup analysis for depressed adolescents at baseline (>27 MFQ), we found a larger clinical effect (Cohen’s effect=-0.52; 95% CI -0.86 to -0.17; p=0·0033) and a lower ICER of £5,255 per QALY with a probability of DISCOVER being cost-effective compared to TAU of between 89% and 95%. Adverse events (serious adverse events) reported 11 (2) compared to 16 (2) in the DISCOVER and TAU arms.

The DISCOVER programme was both clinically-effective in reducing symptoms of depression and cost-effective. This intervention could be utilised as an early intervention by the NHS in schools.

Funding: NIHR HTA (NIHR127951).
Original languageEnglish
JournalThe Lancet Psychiatry
Publication statusAccepted/In press - 21 Mar 2024

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