a model of investigation that intends to ascertain an estimate of the level of genetic potential of a chosen attribute or illness by similar measures as comparing the frequency of the attribute or illness in those who have been adopted and in their birth moms and dads and adoptive family units. For instance, one may possibly put side by side the frequency of schizophrenic disorder in adoptive and natural moms and dads whenever an adopted person has been clinically determined to have the disorder, or one could very well analyze the frequency of schizophrenic disorder amidst adopted persons who have natural moms and dads who have schizophrenic disorder with the frequency amidst adopted persons whose moms and dads don’t have schizophrenic disorder.