dear dr. Múthen, I'm trying to do an EFA on data from 450 patients who completed a survey on patient safety. The .dat file includes all 450 cases; the few missings have been coded as 888888. When I run a simple EFA using Mplus 6.1, only half of the cases are used (n=225). Rebuilding the .dat file did not solve the issue. What can cause this problem?