 Sufficient statistical power can be achieved with relatively small samples (N=20 per subgroup), provided cluster separation is large ({\Delta}=4).
<clarity>  Sufficient statistical power can be achieved with relatively small samples (N=20 per subgroup), provided cluster separation is large ({\Delta}=4).
 Sufficient statistical power was achieved with relatively small samples (N=20 per subgroup), provided cluster separation is large ({\Delta}=4).