I know this is late, but it depends on the OTA Program. I am still in the process of going into either nursing or occupational therapy and currently getting my CNA and working in the heath care field that would work with either profession. I don't think OTAs need the same Critical Thinking level as an LPN or RN. Although they are extremely helpful, they usually have a plan with a patient and continually track progress of the patient. If you decide to become an OT, you would need something closer to an LPN or Rn. An LPN can work in a number of setting and have to deal with more direct care that can vary from day to day or workplace to workplace, while a COTA would work in a number of different types of REHAB or mental care facilities. So to answer your question(s), they would both need to utilize Critical Thinking but an LPN would need to have a great spectrum as they have a more varied profession. This is what I have accessed from working with both LPNs and COTA/OTs.