The rate of posting of results did not differ at three months between trials with or without the intervention : 36/190 ( 19 % ) v 24/189 ( 13 % ) , respectively ( relative risk 1.5 , 95 % confidence interval 0.9 to 2.4 , P = 0.096 ) but did at six months : 46/190 ( 24 % ) v 27/189 ( 14 % ) , 1.7 , 1.1 to 2.6 , P = 0.014 .