The ENDOCARE questionnaire (ECQ): a valid and reliable instrument to measure the patient-centeredness of endometriosis care in Europe. by Dancet, E, Ameye, L, Sermeus, W, Welkenhuysen, M, Nelen, W, Tully, L, De Bie, B, Veit, J, Vedsted-Hansen, H, Zondervan, K, De Cicco, C, Kremer, J, Timmerman, D, D'Hooghe, T