To assess family caregivers' opinions about level of interaction with the environment in their relatives with disorders of consciousness (DOCs) and to explore psychological features of caregivers whose opinions diverge from clinicians' diagnosis.Forty-five family caregivers of 38 DOC inpatients without communication abilities answered 2 questions assessing their opinion about level of interaction with the environment in their relatives. Self-report questionnaires were used to evaluate caregivers' depression, anxiety, psychophysiological disturbances, prolonged grief disorder, coping strategies, quality of perceived needs and social support.Fifteen caregivers (5 relatives of patients in vegetative state and 10 of patients in minimally conscious state) considered their relatives able to communicate, in contrast with clinical diagnosis. These caregivers had significantly higher depressive symptoms, and higher worries about possible death of their relatives with respect to the remaining caregivers.Caregivers of DOC patients detected some interaction with the environment in their relatives more often than care professionals. This is likely related to caregivers' beliefs and expectations, but is also based on observations closer and longer than those possible for physicians. These considerations are important to build a therapeutic alliance with caregivers and to involve them in the diagnostic process and rehabilitative program. (PsycINFO Database Record