If you reverify a root program, the JCL or System Definition file that maps the program to a PSB will be invalidated. If you reverify non-root programs, all call chains leading to them will be analyzed and any JCLs or System Definition files that start corresponding root programs will be invalidated. Make sure to reverify invalidated files.
Conversely, if you change a program-to-PSB mapping inside a JCL or System Definition file, or change the PSB file itself, make sure to reverify the mapped program before reverifying the JCL or System Definition file.
When you rerun IMS Analysis, it will process all complete call chains, starting from all reverified JCLs and System Definition files. You can limit the number of root programs that are re-analyzed in subsequent runs of IMS calls analysis by setting up System Definition files so that they reference one transaction pcf only.