The concept of medical futility is not similar to the concept of persistent therapy. Authors' reply. - Szczeklik W; Krajnik M; Pawlikowski J; Szeroczyńska M; Gajewski P; Kotlińska-Lemieszek A; Aszyk P; Muszala A; Imiela J; Imiela T; Górka J; Kübler A; et al. (Polish archives of internal medicine, 2024)