The posterior mean difference between stimulant and placebo scores for the Conners 3-PS ( Global Index ) was 2.3 ( SD 6.2 ; 95 % credible region -1.0 to 6.1 ; posterior probability that this mean difference was greater than zero was 0.92 ) , and for the Conners 3-T ( Global Index ) the posterior mean difference was 5.9 ( SD 4.5 ; 95 % credible region -3.1 to 14.9 ; posterior probability 0.93 ) .