Crick R P, Daubs J G
Int Ophthalmol. 1980 Dec;3(1):37-41. doi: 10.1007/BF00136212.
We have described the epidemiological analysis of one aspect of the King's College Hospital computerized data base; namely initial intraocular pressure as an indicator of visual field loss. The methods involved the use of the four-fold table to determine sensitivity and specificity at different pressure levels. From these results (1) the changes in the pre and post test probability of field loss are calculated and (2) a 'sensitivity/specificity trade off curve' or 'decision curve' is constructed. In this way the optimal 'cut-off level' or 'operating point' for a population of specific type and composition can be determined. The factors concerned in decision making are always complex but such an approach allows a rational and quantifiable alternative to reliance on clinical impression and intuition. The results have significance in relation to decisions on the management of patients and on population screening programmes for glaucoma.
我们已经描述了对国王学院医院计算机数据库某一方面的流行病学分析；即初始眼压作为视野丧失的一个指标。所采用的方法包括使用四格表来确定不同压力水平下的敏感性和特异性。根据这些结果：（1）计算视野丧失的测试前概率和测试后概率的变化；（2）构建一条“敏感性/特异性权衡曲线”或“决策曲线”。通过这种方式，可以确定特定类型和构成人群的最佳“临界水平”或“操作点”。决策中涉及的因素总是复杂的，但这种方法为依赖临床印象和直觉提供了一种合理且可量化的替代方案。这些结果对于青光眼患者的管理决策和人群筛查计划具有重要意义。
