I am trying to build a model that will predict a specific diagnosis is present. E.g CT chest showing calcification in coronary arteries or MRI showing typical amyloid pattern. I am trying to build the best possible model that would predict the positive scan based on the variables I have like age/gender/co morbidities etc. Do I need ti use a specific package/test or I can start with just logistic regression? And what are things I need to consider before starting a model? Do I need to include all the variables in the start or the one I think will be most relevant?