"Usmle step 2 cs has been in a great demand from the starting till now. The thing which needs to be updated always is Usmle which is done at its best in Target Usmle Step 2 CS. And It is currently in its fifth edition with the aim of updating.
In 2012, when the pattern of the exam changed especially in the step 2 cs patient note format, the change was not updated immediately in the 4th edition. The 5th edition released in 2014 is the current edition as of now (2015 Jan). It has updated patient notes under each long case in the format as expected in the USMLE step 2 cs exam. Most students who have taken the exam express in multiple forums that first aid usmle step 2 cs book covers all types of cases that come in the real exam even though it may not be exactly be the same presentation."
