Roberts described Joseph as an "awkward and very bookish" character, one who struggled to relate to his patients, in contrast to the "happy-go-lucky Sam", which resulted in comedy as "Sam is the antithesis of Joe." He also deemed his character "incredibly honest and morally upright", "a total oddball with all sorts of hang-ups", and as being "very stuck in his ways."
Roberts portrayed Joseph as a "clumsy and extremely intelligent" person, who struggled to connect with his patients, whereas the "lighthearted Sam" served as a comedic contrast. He also characterized his character as "extremely honest and morally sound", "a one-of-a-kind individual with various quirks", and as being "remarkably inflexible."