The efficacy of web-based therapies for chronic pain: a systematic review and meta- analysis The efficacy of web-based therapies for chronic pain: a systematic review and meta- analysis Debora D. Macéa¹; Yasser A.D. Calil 2 ; Felipe Fregni¹ ¹Laboratory of Neuromodulation, Spaulding Rehabilitation Hospital, Harvard Medical School; 2 Faculdade de Medicina da USP Introduction The pooled effect size (standardized mean difference between intervention vs. waiting list group means) from a random effects model was (95% confidence interval: 0.145– 0.424), favoring the web-based intervention compared with the waiting list group, although the effect was small. In addition, these results were not driven by any particular study, as shown by sensitivity analysis. Results from funnel plot argue against publication bias. Finally, the average dropout rate was 26.6%. Chronic pain costs more than $200 billion annually in United States. There is a significant global burden of chronic pain that directly influences quality of life. Cognitive behavior therapy (CBT) is one of the most well-known treatments for chronic pain and were first introduced over 40 years ago. The main principles of CBT for pain management are based on helping the patient to understand how cognition and behavior can affect the pain experience, coping skills training, and cognitive restructuring. One disadvantage of treatment with CBT, mainly in developing countries, is its high costs and difficult accessibility, being often an unavailable treatment. As internet access has grown exponentially, CBT can be administered through internet-based interventions. Our objective was to conduct a systematic review and meta- analysis to quantify the efficacy of web-based interventions for the treatment of patients with chronic pain. Objectives Methods MEDLINE and other databases were searched as data sources. Reference lists were examined for other relevant articles. We included studies that evaluated the effects of web-based interventions on chronic pain using specific scales of pain. Figure 1 – Flowchart of the selection process of peer-reviewed articles for mean pain analysis. Results Table 1 – –Standardized mean differences in VAS from each study comparing after vs. before treatment in the control and intervention groups, on a 0-to-100 scale Schult z, 2007 Lorig, 2002 Lorig, 2006 Hick, 2006 Brattb erg, 2006 Strom, 2000 Berma n, 2008 Lorig, 2008 Buhr man, 2004 Conne llyl, 2006 Devine ni, 2005 Control group Treatm ent group Figure 2 – Forest plot including all the studies analyzed in this meta-analysis, with the pooled effect size (intervention versus waiting-list group) for studies of web-based interventions effects on chronic pain Conclusion In our meta-analysis, we demonstrate a small effect of web- based interventions, when using pain scale as the main outcome. Despite the minor effects and high dropout rates, the decreased costs and minor risk of adverse effects compared with pharmacological treatments support additional studies in chronic pain patients using web-based interventions. Further studies will be important to confirm the effects and determine the best responders to this intervention.