Santori G, Fontana I, Bertocchi M, Gasloli G, Valente U
Department of Transplantation, San Martino University Hospital, Genoa, Italy.
Transplant Proc. 2010 May;42(4):1080-3. doi: 10.1016/j.transproceed.2010.03.036.
Following the example of many Western countries, where a "minimum volume rule" policy has been adopted as a quality parameter for complex surgical procedures, the Italian National Transplant Centre set the minimum number of kidney transplantation procedures/y at 30/center. The number of procedures performed in a single center over a large period may be treated as a time series to evaluate trends, seasonal cycles, and nonsystematic fluctuations. Between January 1, 1983, and December 31, 2007, we performed 1376 procedures in adult or pediatric recipients from living or cadaveric donors. The greatest numbers of cases/y were performed in 1998 (n = 86) followed by 2004 (n = 82), 1996 (n = 75), and 2003 (n = 73). A time series analysis performed using R Statistical Software (Foundation for Statistical Computing, Vienna, Austria), a free software environment for statistical computing and graphics, showed a whole incremental trend after exponential smoothing as well as after seasonal decomposition. However, starting from 2005, we observed a decreased trend in the series. The number of kidney transplants expected to be performed for 2008 by using the Holt-Winters exponential smoothing applied to the period 1983 to 2007 suggested 58 procedures, while in that year there were 52. The time series approach may be helpful to establish a minimum volume/y at a single-center level.
许多西方国家已采用“最小容量规则”政策作为复杂外科手术的质量参数，意大利国家移植中心效仿这一做法，将每个中心每年肾脏移植手术的最低数量设定为30例。在较长时期内单个中心所进行的手术数量可被视为一个时间序列，以评估趋势、季节周期和非系统性波动。在1983年1月1日至2007年12月31日期间，我们对来自活体或尸体供体的成人或儿童受者进行了1376例手术。每年手术例数最多的年份是1998年（n = 86），其次是2004年（n = 82）、1996年（n = 75）和2003年（n = 73）。使用R统计软件（奥地利维也纳统计计算基金会，用于统计计算和绘图的免费软件环境）进行的时间序列分析表明，经过指数平滑以及季节分解后呈现出整体上升趋势。然而，从2005年开始，我们观察到该序列呈下降趋势。运用适用于1983年至2007年期间的霍尔特 - 温特斯指数平滑法预测2008年肾脏移植手术例数为58例，而当年实际为52例。时间序列方法可能有助于在单中心层面确定每年的最小容量。
