Inclusion Criteria:  undergoing TKA for the first time, being scheduled to have unilateral TKA, having surgery for osteoarthritis, having no postoperative complications, fulfilment of discharge criteria after surgery, being aged 18 years or older, being conscious, orientation to place and time, having no hearing or speech problems, ability to understand and speak Turkish, being at least literate, not being diagnosed with any psychiatric diseases and not having a history of cancer.  Exclusion Criteria:  diagnoses of neurological (e.g. Alzheimer's disease) and psychiatric disorders (e.g. schizophrenia) likely to affect cognitive functions, first accepting to participate in the study and then dropping out of the study, development of complications during follow-up (e.g. infection), unavailability when called and lost to follow-up.