## 2 Materials and Methods  
### Survey Development and ADL Items  
For differentiation of utilizing the external robotic arm and upper limb exoskeleton for assistance, it was defined and explained to the survey participants that the external robotic arm will assist as a helper external to the body performing the desired movement or providing and placing the object that is needed for completing the task. It was described that the exoskeleton would be in a completely wearable form to assist the movements of the paralyzed part of the body, including the fingers in the form of a glove. For control of the robot, the subjects were asked to assume a perfect BMI control system and a robot that could perform all of the tasks completely. The subjects were informed about the three categories of BMI technology from non-invasive to invasive to have a concept of BMI; however, for the survey, they were instructed to assume the best BMI system without significant risks. Regarding each different task, it was assumed that the robot was specifically designed for the designated ADL task; therefore, a robot for assisting eating and another robot for assisting brushing teeth may have different forms of hardware and control mechanisms regardless of the total degree of freedom of the robot. It was also assumed that a robot hand or a glove type exoskeleton with precise control is mounted on the robot. They were instructed not to take realizability into consideration, but rather to focus on the importance and necessity of the ADL items themselves.  
Fourteen ADLs were selected for rating in regard to both the external robotic arm and upper limb exoskeleton, and four additional items were selected for exoskeletons. The survey items were extracted from the commonly used ADL assessment tools, such as the modified Barthel Index (MBI) [16] or Functional Independence Measure (FIM) [17], as well as some results from our preliminary research. After the extraction, a professional committee meeting that consisted of four physiatrists, two rehabilitation robot engineers, and two neuroscience engineers reviewed the survey items and selected relevant survey items. The 14 selected ADL items were as follows: (1) washing face, (2) brushing teeth (including squeezing toothpaste), (3) hairdressing (handling hair and combing), (4) dressing (putting on or taking off clothes), (5) eating (using utensils such as spoon or fork, and bringing them to their mouths), (6) handling foods (i.e., peeling a banana, opening a bottle cap, etc.), (7) cleaning (cleaning one's desk), (8) moving close items (from one place to another on a desk or a table), (9) using a smartphone (using a smartphone or smart tablet, including holding the device with one hand and manipulation of the screen with the other hand), (10) using a computer (using a computer, more focusing on using the keyboard), (11) making phone calls (dialing and receiving a phone call), (12) writing, (13) switch control, and (14) using a purse (putting in and taking out bills and cards from a purse/wallet). The four additional items for exoskeletons were as follows: (1) transfer (assisting bed to chair, chair to standing, etc.), (2) toilet use (hygiene process), (3) self-exercise (range-of-motion exercises of the upper extremity), and (4) wheelchair control (both manual and electric). These items were not included for the external robotic arm category and considered not appropriate to be assisted by an external robot, and the assistance method was clearly explained to the survey participants. The survey form and detailed instructions are provided in the Appendix A.