OBJECTIVE: To ensure accuracy in recording the Barthel Index (BI) in older people, it is essential to determine who is best placed to administer the index. The aim of this study was to compare doctors' and nurses' reliability in scoring the BI.
METHODS: Sixty-five consecutive patients admitted to an older adult rehabilitation unit were assessed using the BI. Four raters recorded the BI on all patients. BI scores were compared for equivalence on the level of agreement between raters.
RESULTS: Near-perfect correlation in the total scores between raters indicated that the final score is reliable. There was a statistically significant bias by doctors who gave a higher BI score than nurses with a mean difference of 1.2 (95% confidence interval). Nurses demonstrated good and very good agreement on all 10 items, whereas doctors demonstrated good agreement on only 5 items.
CONCLUSION: The BI is highly reliable when recorded by nurses with low interrater variation, whereas between doctors, there is greater variation. When assessing older adult's activities of daily living, there is greater interrater reliability in the BI score when the patient is observed performing the activities of daily living compared to the self-report method.