IMPACT Statistical Analysis Plan
Creators: name: Barrett, Barbara
name: Byford, Sarah
name: Holland, Fiona
name: Roberts, Chris
Publisher: name: figshare
Year: 2016
Subjects: subject: Clinical Psychology
subject: 111714 Mental Health
subject: FOS: Health sciences
subject: FOS: Health sciences

description: This document considers the final statistical and health economic analyses for the IMPACT trial. <br>The IMPACT Study investigated whether Cognitive Behavioural Therapy or Short Term Psychoanalytic Therapy is superior in reducing relapse compared with Specialist Clinical Care in adolescents with moderate to severe unipolar major depression.<br>The purpose of the SAP is to document the confirmatory statistical analyses of the trial thereby controlling for statistical analyses bias. The statistical analyses follow the principles of ICH E9.<br>The protocol of the paper is published in Goodyer IM et al Improving mood with psychoanalytic and cognitive therapies (IMPACT): a pragmatic effectiveness superiority trial to investigate whether specialised psychological treatment reduces the risk for relapse in adolescents with moderate to severe unipolar depression: study protocol for a randomised controlled trial. Trials. 2011 Jul 13;12:175. doi: 10.1186/1745-6215-12-175.<br>PROTOCOL PAPER ABSTRACT<br>BACKGROUND:Up to 70% of adolescents with moderate to severe unipolar major depression respond to psychological treatment plus Fluoxetine (20-50 mg) with symptom reduction and improved social function reported by 24 weeks after beginning treatment. Around 20% of non responders appear treatment resistant and 30% of responders relapse within 2 years. The specific efficacy of different psychological therapies and the moderators and mediators that influence risk for relapse are unclear. The cost-effectiveness and safety of psychological treatments remain poorly evaluated.<br>METHODS/DESIGN:Improving Mood with Psychoanalytic and Cognitive Therapies, the IMPACT Study, will determine whether Cognitive Behavioural Therapy or Short Term Psychoanalytic Therapy is superior in reducing relapse compared with Specialist Clinical Care. The study is a multicentre pragmatic effectiveness superiority randomised clinical trial: Cognitive Behavioural Therapy consists of 20 sessions over 30 weeks, Short Term Psychoanalytic Psychotherapy 30 sessions over 30 weeks and Specialist Clinical Care 12 sessions over 20 weeks. We will recruit 540 patients with 180 randomised to each arm. Patients will be reassessed at 6, 12, 36, 52 and 86 weeks. Methodological aspects of the study are systematic recruitment, explicit inclusion criteria, reliability checks of assessments with control for rater shift, research assessors independent of treatment team and blind to randomization, analysis by intention to treat, data management using remote data entry, measures of quality assurance, advanced statistical analysis, manualised treatment protocols, checks of adherence and competence of therapists and assessment of cost-effectiveness. We will also determine whether time to recovery and/or relapse are moderated by variations in brain structure and function and selected genetic and hormone biomarkers taken at entry.DISCUSSION:The objective of this clinical trial is to determine whether there are specific effects of specialist psychotherapy that reduce relapse in unipolar major depression in adolescents and thereby costs of treatment to society. We also anticipate being able to utilise psychotherapy experience, neuroimaging, genetic and hormone measures to reveal what techniques and their protocols may work best for which patients.TRIAL REGISTRATION:Current Controlled Trials ISRCTN83033550.