I am working on RCT to evaluate the role of pharmacists training on management of diabetic patients. HbA1c was measured before and after the intervention. Two groups of patients (Intervention and control) were recruited. Duration of intervention was 3 months. The wash out duration was 1 month, then cross over was done; the intervention group become a control group and the control become an intervention one. How can i calculate the carry out effect of this intervention upon the intervention group at the end of the second phase?