Objective: To study the agreement between the level of satisfaction of patients and their families referred to the care and attention received during admission to the ICU. Design: A prospective, 5-month observational and descriptive study was carried out. Setting: ICU of Marques de Valdecilla University Hospital, Santander (Spain). Subjects: Adult patients with an ICU stay longer than 24 h, who were discharged to the ward during the period of the study, and their relatives. Intervention: Instrument: FS-ICU 34 for assessing family satisfaction, and an adaptation of the FS-ICU 34 for patients. The Cohen kappa index was calculated to assess agreement between answers. Results: An analysis was made of the questionnaires from one same family unit, obtaining 148 pairs of surveys (296 questionnaires). The kappa index ranged between 0.278-0.558, which is indicative of mild to moderate agreement. Conclusions: The families of patients admitted to the ICU cannot be regarded as good proxies, at least for competent patients. In such cases, we must refer to these patients in order to obtain first hand information on their feelings, perceptions and experiences during admission to the ICU. Only when patients are unable to actively participate in the care process should their relatives be consulted. (C) 2016 Elsevier Espana, S.L.U. y SEMICYUC. All rights reserved.