CREATE TABLE table_203_437 (id DECIMAL, "year" DECIMAL, "laureate" TEXT, "relation" TEXT, "category" TEXT, "rationale" TEXT)

who was the first laureate in physiology or medicine ?
SELECT "laureate" FROM table_203_437 WHERE "category" = 'physiology or medicine' ORDER BY "year" LIMIT 1
SELECT "laureate" FROM "table_203_437" WHERE "category" = 'physiology or medicine' ORDER BY "year" NULLS FIRST LIMIT 1