Patient care experiences represent opportunities for establishing theories, testable hypotheses, and data to assess the potential use of osteopathic manipulative treatment in various disease conditions. The re-analysis of Bandeen's 1949 raw data described herein summarizes the effects of osteopathic manipulative treatment involving pancreatic stimulatory and inhibitory techniques in diabetic and non-diabetic patients seen over a 25-year period of clinical practice. Bandeen's data demonstrate a reduction in blood glucose levels at 30 and 60 minutes following pancreatic stimulation in 150 diabetic patients, and an elevation in blood glucose levels at 30 and 60 minutes following pancreatic inhibition in 40 non-diabetic patients. Such patient-oriented research conducted during the classic era of osteopathy in the United States provides a foundation and data for generating hypotheses about the potential mechanisms of action of osteopathic manipulative treatment. Osteopathic investigators would be well-served to rediscover the classic osteopathic literature to help advance contemporary evidence-based medicine.