计算混合样本似然率方法的分析与探讨

摘要

目的：对混合样本似然率的四种计算方法进行分析和探讨。方法以2013年CNAS-T0757能力验证的1例样本为例，使用四种常用方法（无限制性组合的似然率法、Clayton等的计算方法、p2定律的计算方法和ISFG推荐方法）分别计算似然率，并进行比较。结果 Clayton等的计算方法、ISFG推荐方法得出的似然率最高，其次为无限制性组合的似然率法得出的结果，p2定律得出的似然率最低。结论无限制性组合的似然率法最大程度兼顾了信息的保留及鉴定人的保护。%Objective To analyze and discuss four methods of calculating likelihood ratio of DNA mixture. Methods In the case with CNAS-T0757 proficiency testing in 2013, the likelihood ratios were calculated and compared among four methods, including unrestricted combinatorial method, Clayton’s method, p2 principle method, and recommendations fromISFG . Results The likelihood ratios were maximumby Clayton’s method and recommendations fromISFG , followed by result of the unrestricted combinational method. The minimu mlikelihood ratio was obtained by p2 principle. Conclusion The unrestricted combi-national method could give furthest consideration to both information preservation and appraiser protection.