Thank you for your response. The article you attached was relly inspiring to me. Color coding system is actualy one of the most promissing design ideas that I have so far, since my thesis project is adressing patients with lmited English literacy. Colors sometimes speak more than languages do in the circumstance like this. However, after reading this article, I reallized that things are not as easy as I though. There are a lot of things that I have to take into a consideration. One of the things I noticed is that I have to deal with the mental aspects of medical care as well as physical aspects of it. As the artice says, some of patients refuse to wear those wrist bands because they are embassased to put on them . They don't want others to know what types of health conditions they have which is really private matters to them. "Being labeled by colors" somewhat makes them to feel like they are treated like objects. There is no respect for patient's dignity. For my thesis project, I want to pay a speciall attention to this sensitive matter as well.