Instituto Aragonés de Ciencias de la Salud, Instituto de Investigación Sanitaria Aragón, Zaragoza, Spain.
BMC Cancer. 2011 Apr 19;11:145. doi: 10.1186/1471-2407-11-145.
Geographical variations in medical practice are expected to be small when the evidence about the effectiveness and safety of a particular technology is abundant. This would be the case of the prescription of conservative surgery in breast cancer patients. In these cases, when variation is larger than expected by need, socioeconomic factors have been argued as an explanation.
Using an ecologic design, our study aims at describing the variability in the use of surgical conservative versus non-conservative treatment. Additionally, it seeks to establish whether the socioeconomic status of the healthcare area influences the use of one or the other technique.
81,868 mastectomies performed between 2002 and 2006 in 180 healthcare areas were studied. Standardized utilization rates of breast cancer conservative (CS) and non-conservative (NCS) procedures were estimated as well as the variation among areas, using small area statistics. Concentration curves and dominance tests were estimated to determine the impact of income and instruction levels in the healthcare area on surgery rates. Multilevel analyses were performed to determine the influence of regional policies.
Variation in the use of CS was massive (4-fold factor between the highest and the lowest rate) and larger than in the case of NCS (2-fold), whichever the age group. Healthcare areas with higher economic and instruction levels showed highest rates of CS, regardless of the age group, while areas with lower economic and educational levels yielded higher rates of NCS interventions. Living in a particular Autonomous Community (AC), explained a substantial part of the CS residual variance (up to a 60.5% in women 50 to 70).
The place where a woman lives -income level and regional policies- explain the unexpectedly high variation found in utilization rates of conservative breast cancer surgery.
当特定技术的有效性和安全性证据充足时，医疗实践中的地域差异预计会很小。在乳腺癌患者采用保守手术治疗的情况下就是如此。在这些情况下，如果变化大于需求预期，则社会经济因素被认为是一种解释。
本研究采用生态设计，旨在描述手术保守治疗与非保守治疗的使用变化情况。此外，它试图确定医疗保健区域的社会经济地位是否会影响使用一种或另一种技术。
研究了 2002 年至 2006 年间在 180 个医疗保健区域进行的 81868 例乳房切除术。使用小区域统计数据估计了乳腺癌保守（CS）和非保守（NCS）手术的标准化利用率，以及区域之间的变化。估计了集中曲线和优势测试，以确定医疗保健区域的收入和教育水平对手术率的影响。进行了多水平分析以确定区域政策的影响。
CS 的使用变化很大（最高和最低比率相差 4 倍），且大于 NCS 的变化（2 倍），无论年龄组如何。经济和教育水平较高的医疗保健区域，无论年龄组如何，CS 率都较高，而经济和教育水平较低的区域则倾向于采用 NCS 干预。居住在特定自治区（AC），可以解释 CS 残余方差的很大一部分（在 50 至 70 岁的女性中高达 60.5%）。
女性居住的地方——收入水平和区域政策——解释了保守性乳腺癌手术利用率中发现的异常高的变化。
