Other tests are often performed to detect anatomic defects. Children are prepared for these tests as appropriate for their age. Children who are old enough to understand need an explanation of the procedure, its purpose, and what they will experience. Sometime a simple description of the urinary system is helpful. For children under 3 to 4 years of age, the procedure can be explained using a doll. For those who are older, a simple drawing of the bladder, urethra, ureters, and kidneys makes the explanation more understandable. Especially with preschool children, the nurse must clarify that the urinary tract is separate from any sexual function and that the test is for a problem that they did not cause. It is not uncommon for children to associate blame for perceived wrongdoing or unacceptable thoughts with the reason for the illness or tests.