The prediabetic patients showed improvement in self-efficacy for modifying diet ( mean 5.31 , SD 2.81 vs mean 8.53 , SD 2.25 ) , increasing physical activities ( mean 4.52 , SD 3.35 vs mean 8.06 , SD 2.38 ) , engaging relatives ( mean 3.93 , SD 3.54 vs mean 6.93 , SD 2.67 ) , and knowledge about diabetes and risks of an imbalanced diet and inadequate physical activity .