BackgroundTourette syndrome (TS) is a neurodevelopmental condition characterised by chronic motor and vocal tics affecting up to 1% of school-age children and young people and is associated with significant distress and psychosocial impairment.ObjectiveTo conduct a systematic review of the benefits and risks of pharmacological, behavioural and physical interventions for tics in children and young people with TS (part 1) and to explore the experience of treatment and services from the perspective of young people with TS and their parents (part 2).Data SourcesFor the systematic reviews (parts 1 and 2), mainstream bibliographic databases, The Cochrane Library, education, social care and grey literature databases were searched using subject headings and text words for tic* and Tourette* from database inception to January 2013.Review/research methodsFor part 1, randomised controlled trials and controlled before-and-after studies of pharmacological, behavioural or physical interventions in children or young people (aged < 18 years) with TS or chronic tic disorder were included. Mixed studies and studies in adults were considered as supporting evidence. Risk of bias associated with each study was evaluated using the Cochrane tool. When there was sufficient data, random-effects meta-analysis was used to synthesize the evidence and the quality of evidence for each outcome was assessed using the Grading of Recommendations Assessment, Development and Evaluation approach. For part 2, qualitative studies and survey literature conducted in populations of children/young people with TS or their carers or in health professionals with experience of treating TS were included in the qualitative review. Results were synthesized narratively. In addition, a national parent/carer survey was conducted via the Tourettes Action website. Participants included parents of children and young people with TS aged under 18 years. Participants (young people with TS aged 10–17 years) for the in-depth interviews were recruited via a national survey and specialist Tourettes clinics in the UK.ResultsFor part 1, 70 studies were included in the quantitative systematic review. The evidence suggested that for treating tics in children and young people with TS, antipsychotic drugs [standardised mean difference (SMD) –0.74, 95% confidence interval (CI) –1.08 to –0.41;n = 75] and noradrenergic agents [clonidine (Dixarit^®, Boehringer Ingelheim) and guanfacine: SMD –0.72, 95% CI –1.03 to –0.40;n = 164] are effective in the short term. There was little difference among antipsychotics in terms of benefits, but adverse effect profiles do differ. Habit reversal training (HRT)/comprehensive behavioural intervention for tics (CBIT) was also shown to be effective (SMD –0.64, 95% CI –0.99 to –0.29;n = 133). For part 2, 295 parents/carers of children and young people with TS contributed useable survey data. Forty young people with TS participated in in-depth interviews. Four studies were in the qualitative review. Key themes were difficulties in accessing specialist care and behavioural interventions, delay in diagnosis, importance of anxiety and emotional symptoms, lack of provision of information to schools and inadequate information regarding medication and adverse effects.LimitationsThe number and quality of clinical trials is low and this downgrades the strength of the evidence and conclusions.ConclusionsAntipsychotics, noradrenergic agents and HRT/CBIT are effective in reducing tics in children and young people with TS. The balance of benefits and harms favours the most commonly used medications: risperidone (Risperdal^®, Janssen), clonidine and aripiprazole (Abilify^®, Otsuka). Larger and better-conducted trials addressing important clinical uncertainties are required. Further research is needed into widening access to behavioural interventions through use of technology including mobile applications (‘apps’) and video consultation.Study registrationThis study is registered as PROSPERO CRD42012002059.FundingThe National Institute for Health Research Health Technology Assessment programme.