Получение ошибки 'столбец не существует' в PostgreSQL 11.0 при выполнении оператора CASE

Я пытаюсь обновить значение столбца таблицы PostgreSQL на основе приведенного ниже оператора case.

UPDATE testschema.tbl
SET route_of_admin_class = CASE
         WHEN route_of_admin = 'n/a' then NULL
         
         WHEN route_of_admin is null then null
         
         WHEN route_of_admin = '-' then '(null)'

         WHEN route_of_admin IN ("other", 
                                "liquids, oils",
                                "liquids, combination pack",
                                "vials, dry",
                                "vials",
                                "vials, instillation",
                                "liquids, metered-dose",
                                "liquids, suspensions",
                                "powders, medicinal/pharmaceutical solid substances",
                                "powders, dusting",
                                "vials, cartridges",
                                "liquids, syrups",
                                "powders, granules",
                                "other special forms - foams",
                                "liquids, collodion/lacquers",
                                "vials, unit dose cartridges",
                                "powders, unit dose",
                                "vials, other",
                                "powders, other powders/granules",
                                "vials, combination pack",
                                "liquids",
                                "powders, soluble",
                                "special solid forms, ocular therapeutic systems",
                                "powders",
                                "special solid forms, other",
                                "liquids, emulsions",
                                "liquids, unit dose",
                                "medical aids - diagnostic tests excluding sticks",
                                "other special forms - other",
                                "other special forms - food not ready to eat",
                                "-",
                                "single-use",
                                "single-dose",
                                "multidose",
                                "interstitial",
                                "for rx compounding" ) THEN 'other'
           else route_of_admin 
           end

Я получаю следующую ошибку при выполнении вышеуказанного оператора.

[Code: 0, SQL State: 42703]  ERROR: column "other" does not exist
  Position: 286  [Script position: 8218 - 8226]

Строка, в которой скрипт выдает ошибку:

WHEN route_of_admin IN ("other", 
                                "liquids, oils",
                                "liquids, combination pack",
                                "vials, dry",...

Любая помощь высоко ценится!!