Boys are twice as likely as girls in the U.S. and Asia (mostly Japan) to receive recombinant human growth hormone (rhGH) for growth hormone deficiency, illnesses that affect height, and short stature of a non-medical nature. A smaller gender difference exists in Europe, Australia and New Zealand, but in the rest of the world short boys and girls are treated at the same rate. This indicates a likely cultural bias for male height in some countries.