The difference between this and the full-interruption test is that the primary production processing of the business does not stop; the test processing runs in parallel to the real processing. This is the most common type of disaster recovery plan testing.
A checklist test is only considered a preliminary step to a real test.
In a structured walk-through test, business unit management representatives meet to walk through the plan, ensuring it accurately reflects the organization’s ability to recover successfully, at least on paper.
A simulation test is aimed at testing the ability of the personnel to respond to a simulated disaster, but not recovery process is actually performed.
Source: KRUTZ, Ronald L. & VINES, Russel D., The CISSP Prep Guide: Mastering the Ten Domains of Computer Security, John Wiley & Sons, 2001, Chapter 8: Business Continuity Planning and Disaster Recovery Planning (page 289).