Freedman L S, Green S B, Byar D P
Biometry Branch, DCPC, National Cancer Institute, Bethesda, Maryland 20892.
Stat Med. 1990 Aug;9(8):943-52. doi: 10.1002/sim.4780090810.
COMMIT (Community Intervention Trial for Smoking Cessation) is a randomized study employing a matched pairs design. Pairs of communities were selected on the basis of their geographical proximity and were chosen to be matched on variables strongly expected to relate to the outcome variable, the smoking quit rate. However, quantitative information was not available to evaluate the efficiency gain from matching. We have used baseline smoking quit rates in the communities as a surrogate for the outcome measure to evaluate the gain in efficiency from the matching. Our method takes account of the possible imperfection of the surrogate as a representative of the true outcome. The method estimates an efficiency gain of at least 50 per cent using the matched design. We also evaluate the further gains in efficiency which would be made by using the baseline quit rate to balance the randomization.
戒烟社区干预试验（COMMIT）是一项采用配对设计的随机研究。根据地理位置相近的原则选择成对的社区，并选择在与结果变量（戒烟率）密切相关的变量上进行匹配。然而，没有定量信息来评估匹配带来的效率提升。我们使用社区的基线戒烟率作为结果指标的替代指标，以评估匹配带来的效率提升。我们的方法考虑到了替代指标作为真实结果代表可能存在的不完美性。该方法估计，使用配对设计的效率提升至少为50%。我们还评估了使用基线戒烟率来平衡随机化所带来的进一步效率提升。
