Friend of mine is going to be having some medical procedures done around boards time. She wants to know if she can do CP only now and AP only later, and are the CP-only/AP-only exams any harder than combined AP/CP. She is a combined AP/CP resident. For anyone who knows me from this message board, I am in remission from Hodgkin's (finished chemo in Feb) and planning on June boards. I worked through chemo b/c I desperately wanted to finish- now wish me luck on this damn exam.

Thanks everyone.
She can take the AP and CP component at separate sessions if she wishes, although it will cost an extra $1400 to take the exams separately (assuming the prices didnt go up since I took it), not to mention paying twice for airfare, hotels, etc. She will not be board certified until she passes both exams. (Exception: She can, for instance, take the AP exam, pass, then convert one of her CP years or a non-ACGME fellowship year into the flexible third year, but she will have to pay the ABP more money for the AP only certification and she will not be able to count that year towards CP anymore. (ie If she later wants CP certification, she will have to come up with 2 CP years plus a third year that she didnt use for AP certification).
The AP and CP exams are given separately on consecutive days. There is no difference in content or scoring between the exam that the AP/CP resident takes versus the AP only or CP only resident, although there are plenty of conspiracy theories to the contrary. Taking only one exam will not adversely affect the scoring.
However, I would advise to take both exams no matter what, even if she only plans to study for one exam. For an extra $400, she gets the opportunity to avoid coming back to Tampa, and at worst if she fails, she will have taken the exam and know how to prepare properly for it for the next time. I know someone who decided to study only CP, no AP, and took both exams figuring that if she passed AP, it would be a bonus. She ended up passing both the first time.