2. The kids and their parents who referred to growth hormone test will be offered to participate in the study and after signing the consent will be invited for the test. According to accepted protocol, the children arrived after overnight fast, an intravenous line is inserted and blood is taken for measurement of human growth hormone levels, IGF1, thyroid function test, prolactin, cortisol, and adrenaline and then a stimulates substance (glucagon, clonidine or arginine) is given. Afterward blood tests for human growth hormone and cortisol levels, are taken every 30-60 minutes for approximately 3-4 hours after administration of the provocative substance. During the test regular vital signs are monitored according to Protocol.