Trussell T J, Faden R, Hatcher R A
Am J Public Health. 1976 Aug;66(8):761-7. doi: 10.2105/ajph.66.8.761.
Various procedures for estimating the effectiveness of a method of contraception have been devised. These measures, in turn, have been used in populations which differ widely in their propensity to use contraceptives properly. Therefore, a wide array of failure rates is available in the family planning literature. Unfortunately, because of differences in measurement and in choice of population, a random selection of these reported failure rates will not produce a consistent ordinal or cardinal ranking of methods by their effectiveness. Moreover, such a wide variety or reported rates permits the family planning practitioner to choose selectively in order to maximize the attractiveness of his favorite method(s). By surveying family planning personnel in two major cities, we found that they do indeen appear to place the methods they actively dispense in an extremely favorable position. Specifically, they are biased against the traditional contraceptives, foam and the condom. In this paper, we discuss the theoretical underpinnings of the measurement of effectiveness, report the apparent bias in the levels of contraceptive effectiveness reported to the patient, and finally, recommend a procedure for eliminating the jumble of rates in the literature and the consequent confusion among family planning personnel.
人们已经设计出了各种评估避孕方法有效性的程序。这些评估方法又被应用于在正确使用避孕药具的倾向方面差异很大的人群中。因此，计划生育文献中有各种各样的失败率数据。不幸的是，由于测量方法和人群选择的差异，随机选取这些报告的失败率并不能按照有效性对方法产生一致的顺序或基数排名。此外，如此多样的报告率使得计划生育从业者能够进行选择性选择，以最大化其偏好方法的吸引力。通过对两个主要城市的计划生育人员进行调查，我们发现他们确实似乎将自己积极推广的方法置于极其有利的地位。具体而言，他们对传统避孕药具泡沫剂和避孕套存在偏见。在本文中，我们讨论了有效性测量的理论基础，报告了向患者报告的避孕有效性水平中明显存在的偏见，最后，推荐一种程序，以消除文献中各种混乱的比率以及计划生育人员随之产生的困惑。
