1. Background Methods Use of free to use social media to disseminate information in healthcare has increased, but evidence of the effect of this effort is limited. The Cochrane Schizophrenia Group produces and maintains systematic reviews of randomised trials of interventions for schizophrenia and related psychotic illnesses. Abstracts and plain language summaries are freely available. We evaluated a randomised controlled trial of tweeting précis of Cochrane Schizophrenia Group systematic reviews. Conclusion Use of social media was effective for dissemination of evidence in an area of health care that is not particularly high profile. Visits to the target site were more and the time spent on the page longer. We cannot tell if that interest translated into better care more in line with best evidence but ‘product placement’ of good evidence is an important step in the right direction. Results Example of the three tweets relating to same review i.#Clozapine combined with different #antipsychotic #drugs for #treatment resistant #schizophrenia http://ow.ly/yaKAUhttp://ow.ly/yaKAU ii. How effective is #clozapine in addition to another #antipsychotics at treating 'hard to treat' #schizophrenia? http://ow.ly/yaKAU http://ow.ly/yaKAU iii. Not clear if combining #clozapine with other #antipsychotics is effective for #treatment resistant #schizophrenia http://ow.ly/yaKAU http://ow.ly/yaKAU Control (n=85) Twitter (n=85) Adjusted a effect 95% CI Primary outcome All page views Total4491162 Incidence rate5.2813.672.71 b 2.20 to 3.33 Secondary outcomes Unique page views Total4031058 Incidence rate4.7412.452.74 b 2.24 to 3.35 Entrances Total260821 Incidence rate3.069.663.36 b 2.68 to 4.22 100% of visits were single page No5371 Yes24140.41 c 0.19 to 0.88 Direct click visits Total26168 Incidence rate0.311.986.74 b 4.11 to 11.08 Twitter referrals Total0297 Incidence rate03.49-- Any outbound click events No6039 Yes25463.20 c 1.63 to 6.31 Time on page in seconds arithmetic mean (SD) 147 (232) 164 (210) Median (min, max) 51 (0, 1283) 109 (0, 1610) geometric mean31762.47 d 1.32 to 4.61 Study setting This study was conducted entirely on the internet. The participant Plain Language Summaries (PLS) were all freely available at www.summaries.cochrane.org, the intervention was delivered via two social media platforms (Twitter and Weibo) and outcome data collected using Google Analytics.www.summaries.cochrane.org Intervention group Reviews in the intervention group were tweeted in English, by the Cochrane Schizophrenia Group, three times on the same day at 10:30, 13:00 and 15:00 GMT as guided by the SocialBro web tool and eight hours later in China, in Mandarin, via Weibo. Control group Reviews in the control group were not tweeted by the Cochrane Schizophrenia Group. Outcomes The primary outcome was total number of visits to the relevant Cochrane summary page in the 7days following the intervention (including the day of tweeting) as reported on Google Analytics. For reviews in the control arm, the seven day follow up period was the same as for the intervention review with which it had been randomly paired. Trial Registration number: ISRCTN84658943 Following randomisation of 170 reviews, intervention group Tweets were posted between 1 st July 2014 and 13 th January 2015. There was strong evidence of an effect of the intervention on the primary and all of the secondary outcomes (Table). a Adjusted for baseline activity and day of week; b Incidence rate ratio; c Odds ratio; d Ratio of geometric means Table: Primary and Secondary outcomes comparing Twitter and Control groups.