BACKGROUND:Specific clinical interventions are needed to reduce wrong-site surgery, which is a rare but potentially disastrous clinical error. Risk factors contributing to wrong-site surgery are variable and complex. The introduction of organisational and professional clinical strategies may have a role in minimising wrong-site surgery. OBJECTIVES:To evaluate the effectiveness of organisational and professional interventions for reducing wrong-site surgery (including wrong-site, wrong-side, wrong-procedure and wrong-patient surgery), including non-surgical invasive procedures such as regional blocks, dermatological, obstetric and dental procedures and emergency surgical procedures not undertaken within the operating theatre. SEARCH METHODS:We searched the following electronic databases: the Cochrane Effective Practice and Organisation of Care (EPOC) Group Specialised Register (June 2011), the Cochrane Central Register of Controlled Trials (The Cochrane Library 2011, Issue 6), MEDLINE (1948-June 2011), EMBASE (1947-June 2011), CINAHL (1980-June 2011), Dissertations and Theses (1861-June 2011), African Index Medicus, Latin American and Caribbean Health Sciences database, Virtual Health Library, Pan American Health Organization Database and the World Health Organization Library Information System. A grey literature search was conducted. Database searches were conducted June 2011. SELECTION CRITERIA:We included randomised controlled trials (RCTs), non-randomised controlled trials, controlled before-after studies (CBAs) with at least two intervention and control sites, and interrupted-time-series (ITS) studies where the intervention time was clearly defined and there were at least three data points before and three after the intervention. Studies evaluated the effectiveness of organisational and professional interventions for reducing wrong-site surgery, including wrong site, wrong side and wrong procedure. Participants included all healthcare professionals providing care to surgical patients; studies where patients were involved to avoid the incorrect procedures or studies with interventions addressed to healthcare managers, administrators, stakeholders or health insurers. DATA COLLECTION AND ANALYSIS:Two review authors independently assessed the quality and abstracted data of all eligible studies using a standardised data extraction form, modified from the Cochrane EPOC checklists. We contacted study authors for additional information. MAIN RESULTS:We included one study in this review. One ITS study evaluated a targeted educational intervention aiming at reducing the incidence of wrong-site tooth extractions. The intervention included examination of previous cases of wrong-site tooth extractions, educational intervention including a presentation of cases of erroneous extractions, explanation of relevant clinical guidelines and feedback by an instructor. Data was re-analysed using the Prais-Winsten time series and the change in level for annual number of mishaps was statistically significant at -4.52 (95% confidence interval (CI) -6.83 to -2.217) (standard error (SE) 0.5380). The change in slope was statistically significant at -1.16 (95% CI -2.22 to -0.10) (SE 0.2472; P < 0.05). AUTHORS' CONCLUSIONS:The findings of this review identified one ITS study for a non-medical procedure conducted in a dental outpatient setting. The study suggested that the use of a specific educational intervention, in the above-mentioned context, which targets junior dental staff using a training session that included cases of wrong-site surgery, presentation of clinical guidelines and feedback by the instructor, was associated with a reduction in the incidence of wrong-site tooth extractions. Given the nature of the intervention in a very specific population, application of these results to a broader population undergoing other forms of surgery or invasive procedures should be undertaken cautiously.