01188nas a2200133   4500008003900000245006600039210006500105300001200170490000700182520079400189100001300983700001300996856004501009       2018                          d00aConstructing Shadow Tests in Variable-Length Adaptive Testing0 aConstructing Shadow Tests in VariableLength Adaptive Testing  a538-5520 v423 aImposing content constraints is very important in most operational computerized adaptive testing (CAT) programs in educational measurement. Shadow test approach to CAT (Shadow CAT) offers an elegant solution to imposing statistical and nonstatistical constraints by projecting future consequences of item selection. The original form of Shadow CAT presumes fixed test lengths. The goal of the current study was to extend Shadow CAT to tests under variable-length termination conditions and evaluate its performance relative to other content balancing approaches. The study demonstrated the feasibility of constructing Shadow CAT with variable test lengths and in operational CAT programs. The results indicated the superiority of the approach compared with other content balancing methods.1 aDiao, Qi1 aRen, Hao  uhttps://doi.org/10.1177/0146621617753736