Although common among the hospitalized frail elderly, malnutrition is often unrecognized by clinicians, and its identification is frought with difficulty due to inadequate nutritional assessment methods and standards. This study compared the use of percent ideal body weight (%IBW) and anthropometry in the assessment of malnutrition in the hospitalized frail elderly. Approximately 45% of patients studied had at least two anthropometric measurements below the 5th percentile, a level reflecting severe malnutrition. However, only 28% of patients were found to be less than 90% IBW, a level reflecting only mild to severe changes in body weight. Serum albumin was below normal (