Delgado-Rodríguez M, Gómez Olmedo M, Bueno Cavanillas A, Gálvez Vargas R
Cátedra de medicina preventiva y salud pública, Facultad de Medicina, Universidad de Cantabria, Santander.
Gac Sanit. 1997 May-Jun;11(3):136-42. doi: 10.1016/s0213-9111(97)71289-5.
A new index the adequacy of prenatal care utilization (APNCU) index, has been proposed to provide a more accurate and comprehensive measure of antenatal care use than the widely used Kessner index. To better understand the value of the two above mentioned indexes as predictors of preterm delivery, we examined their ability to predict women who will or will not deliver before 37 weeks of gestation.
A case-control study was performed, including 207 cases and 381 controls. Prenatal care was assessed on the basis of the two above mentioned indexes, both taking into account the number of prenatal care visits, the date of the first visit and gestational age. Multiple-factor adjusted odds ratios and their 95% confidence intervals were estimated using logistic regression methods.
The Kessner index showed a lineal trend with both crude and adjusted for (the APNCU index) estimates of preterm delivery risk. The APNCU index did not show any linear trend with adjusted for (the Kessner index) estimates of preterm delivery risk. To assess whether the Kessner index added explanatory information to the APNCU index (or vice versa), the APNCU index was regressed on the Kessner index (and viceversa), and a set of residuals was computed for both indexes. In logistic regression analyses, the residuals of Kessner added meaningful information to the APNCU index, whereas the residuals of the APNCU index did not add any relevant information to the Kessner index. There results remained unchanged after controlling for several confounders.
A variation in the definition of adequate prenatal care use changes the association between prenatal care and preterm delivery. The Kessner index showed a better ability for discriminating and predicting the risk of preterm delivery.
一种新的产前保健利用充分性（APNCU）指数已被提出，旨在提供一种比广泛使用的凯斯纳指数更准确、更全面的产前保健利用衡量指标。为了更好地理解上述两种指数作为早产预测指标的价值，我们研究了它们预测妊娠37周前分娩或未分娩女性的能力。
进行了一项病例对照研究，包括207例病例和381例对照。根据上述两种指数对产前保健进行评估，同时考虑产前检查次数、首次就诊日期和孕周。使用逻辑回归方法估计多因素调整后的优势比及其95%置信区间。
凯斯纳指数在早产风险的粗估计和调整估计（针对APNCU指数）方面均呈现线性趋势。APNCU指数在调整估计（针对凯斯纳指数）的早产风险方面未显示任何线性趋势。为了评估凯斯纳指数是否为APNCU指数增加了解释性信息（反之亦然），对APNCU指数与凯斯纳指数进行回归分析（反之亦然），并为两个指数计算了一组残差。在逻辑回归分析中，凯斯纳指数的残差为APNCU指数增加了有意义的信息，而APNCU指数的残差未为凯斯纳指数增加任何相关信息。在控制了几个混杂因素后，这些结果保持不变。
适当产前保健利用定义的变化会改变产前保健与早产之间的关联。凯斯纳指数在区分和预测早产风险方面表现出更好的能力。
