Evaluation of a command-line parser-based order entry pathway for the Department of Veterans Affairs electronic patient record.

OBJECTIVE: To improve and simplify electronic order entry in an existing electronic patient record, the authors developed an alternative system for entering orders, which is based on a command- interface using robust and simple natural-language techniques. DESIGN: The authors conducted a randomized evaluation of the new entry pathway, measuring time to complete a standard set of orders, and users' satisfaction measured by questionnaire. A group of 16 physician volunteers from the staff of the Department of Veterans Affairs Puget Sound Health Care System-Seattle Division participated in the evaluation. RESULTS: Thirteen of the 16 physicians (81%) were able to enter medical orders more quickly using the natural-language-based entry system than the standard graphical user interface that uses menus and dialogs (mean time spared, 16.06 +/- 4.52 minutes; P=0.029). Compared with the graphical user interface, the command--based pathway was perceived as easier to learn (P<0.01), was considered easier to use and faster (P<0.01), and was rated better overall (P<0.05). CONCLUSION: Physicians found the command- interface easier to learn and faster to use than the usual menu-driven system. The major advantage of the system is that it combines an intuitive graphical user interface with the power and speed of a natural-language analyzer.

Studies on the development of human acute myeloid leukaemia xenografts in immune-deprived mice: comparison with cells in short-term culture.

Human AML cells from the blood of a series of patients have been implanted subcutaneously into mice immune-suppressed by thymectomy and total-body irradiation. Solid tumours resulted from 18 out of 19 samples and their growth was compared with the proliferation of AML cells in culture. In 17 cases tumours grew to a maximum size and then spontaneously regressed. Cells from one patient produced tumours which did not regress and could be retransplanted into freshly immune-suppressed mice. Cells from a human promyelocytic cell line (HL60) also produced nonregressing and retransplantantable tumours. Normal human mononuclear bone marrow cells implanted s.c. produced a growth pattern similar to that of the majority of AML cells. A second inoculum of AML cells into animals with regressing tumours also produced tumours and thus regression cannot be accounted for on the basis of returning immunity. AML cells placed into short-term suspension culture invariably matured to monocyte/macrophage type cells and/or granulocytic cells as identified by cytochemical staining. However, no correlation was observed between proliferation or maturation of cells in culture, and tumour growth in vivo. Cells derived from disaggregated AML tumours also showed evidence of myeloid differentiation suggesting that tumour regression is due to maturation of leukaemic cells.