Kuo Li-cheng, an expert on folklore, says that ketzai booklets are in the tradition of the pienwen style of writing found in the Tunhuang Caves, Sung and Yuan dynasty chiang-chang, taitzu (stories put into rhyme and sung with musical accompaniment) and muyushu. All are forms of popular literature.
民俗學者郭立誠以為，歌仔冊上承敦煌變文、宋元講唱，和彈詞、木魚書一樣，皆是俗文學的一種。