['The present authors examined how patient hand contamination was associated with underlying disease and treatment environment in order to determine effective hand hygiene methods.', 'Samples were collected from inpatients (45 with hematological malignancies, 48 postoperative), outpatients (48 undergoing hemodialysis, 55 on chemotherapy), and 44 individuals living in nursing homes. All participants provided informed consent for study participation. All subjects performed hand hygiene. Before and after hand hygiene, samples of bacteria were collected from the palm of the hand onto agar media. Bacteria were counted and bacterial strains were identified. The authors then collected smear samples from the contralateral palm and measured adenosine triphosphate (ATP) levels.', 'Patient hand contamination was the highest in hemodialysis patients, followed by residents of nursing homes, postoperative patients, patients with cancer receiving chemotherapy, and patients of hematological malignancies. Regardless of the underlying disease and treatment environment, patients were able to reduce the number of bacterial colonies and ATP by proper hand hygiene. Compared with wet wipes, hand washing seemed to remove bacteria more effectively. Methicillin-resistant Staphylococcus aureus (MRSA) was detected in 30 subjects, none of whom were patients of hematological malignancies. Of these, 19 tested negative for MRSA after performing proper hand hygiene.'] Does effectiveness of hand hygiene depend on the patient 's health condition and care environment?