Table 3.53: The change of using heroin before and after intervention Time Using heroin Before intervention After intervention Difference (%) p Yes No Yes No Intervention group 23 (11, 7) 191 (89, 3) 11 (4, 8) 197 (94, 7) 6, 9 0, 023 Control group 26 (11, 8) 195 (88, 2) 21 (100) 188 (90, 0) 1, 8 0, 568 p 0, 737 0, 041 Comments: Evaluating at the intervention clinic and non-intervention clinic, patients still using heroin after intervention in both intervention and control groups showed that there was a significant statistic difference (p<0, 05).