My research involved a questionnaire with open-ended questions, multi-answer multiple choice (select all that apply; entered as "1" for circled answers, "0" for non-circled), and likert scale questions. I want to examine whether there are differences in responses to the survey (especially the likert questions) based on a variety of independent variables. Independent variables are things such as: age, ward number, intervention group (3 colour-coded groups - this was a randomized clinical trial), treating physician/dietitian (entered into SPSS as string variables), presence/absence of dysphagia (entered as binary data 1,2)...and many others.
I would like to treat the likert data as ordinal data rather than interval. This is my first time conducting a research study and would appreciate pointers as to how to even begin the analysis. My limited understanding is that non-parametric tests are more suitable for my scenario.