Duclos Antoine, Voirin Nicolas, Touzet Sandrine, Soardo Pietro, Schott Anne-Marie, Colin Cyrille, Peix Jean-Louis, Lifante Jean-Christophe
Unité d'Étude des Pratiques Professionnelles, Hospices Civils de Lyon, Pôle d'Information Médicale Évaluation Recherche, 162 avenue Lacassagne, F-69424 Lyon Cedex 03, France.
Qual Saf Health Care. 2010 Dec;19(6):e17. doi: 10.1136/qshc.2008.031799. Epub 2010 Apr 8.
Patient-safety monitoring based on health-outcome indicators can lead to misinterpretation of changes in case mix. This study aimed to compare the detection of indicator variations between crude and case-mix-adjusted control charts using data from thyroid surgeries.
The study population included each patient who underwent thyroid surgery in a teaching hospital from January 2006 to May 2008. Patient safety was monitored according to two indicators, which are immediately recognisable postoperative complications: recurrent laryngeal nerve palsy and hypocalcaemia. Each indicator was plotted monthly on a p-control chart using exact limits. The weighted κ statistic was calculated to measure the agreement between crude and case-mix-adjusted control charts.
We evaluated the outcomes of 1405 thyroidectomies. The overall proportions of immediate recurrent laryngeal nerve palsy and hypocalcaemia were 7.4% and 20.5%, respectively. The proportion of agreement in the detection of indicator variations between the crude and case-mix-adjusted p-charts was 95% (95% CI 85% to 99%). The strength of the agreement was κ = 0.76 (95% CI 0.54 to 0.98). The single special cause of variation that occurred was only detected by the case-mix-adjusted p-chart.
There was good agreement in the detection of indicator variations between crude and case-mix-adjusted p-charts. The joint use of crude and adjusted charts seems to be a reasonable approach to increase the accuracy of interpretation of variations in outcome indicators.
基于健康结局指标的患者安全监测可能导致对病例组合变化的误解。本研究旨在使用甲状腺手术数据比较原始控制图和病例组合调整控制图之间指标变化的检测情况。
研究人群包括2006年1月至2008年5月在一家教学医院接受甲状腺手术的每一位患者。根据两个指标监测患者安全，这两个指标是术后立即可识别的并发症：喉返神经麻痹和低钙血症。每个指标每月使用精确界限绘制在p控制图上。计算加权κ统计量以衡量原始控制图和病例组合调整控制图之间的一致性。
我们评估了1405例甲状腺切除术的结果。术后立即发生喉返神经麻痹和低钙血症的总体比例分别为7.4%和20.5%。原始p控制图和病例组合调整p控制图在指标变化检测方面的一致性比例为95%（95%可信区间85%至99%）。一致性强度为κ = 0.76（95%可信区间0.54至0.98）。发生的单一特殊变异原因仅被病例组合调整p控制图检测到。
原始p控制图和病例组合调整p控制图在指标变化检测方面具有良好的一致性。联合使用原始控制图和调整控制图似乎是提高结局指标变化解释准确性的合理方法。
