I took the COMLEX on 6/14 & the USMLE on 6/29. Ill just go topic by topic & compare each & hit on the main differences:
1) Timing: I had approximately 2.5 wks of solid studying after school ended before I took the COMLEX & I wish that I had maybe 3 wks. 2 wks btwn the COMLEX & the USMLE was a little too much time b/c it felt almost like too much time so time stress wasnt a problem (stress motivates me so this was a negative for me).
2) Micro: I had a lot of micro on both of my exams, but especially on the COMLEX (although I had a ridiculous number of STD related questions on the USMLE). The main difference in the two tests was the use of buzzwords. My COMLEX micro question used buzzwords rather frequently (or variations of common buzzwords) & tested mainly over the common associations that you find in MMRS or FA. My USMLE had tons of STD related questions & lots of far out micro such as helminthes, schistosomiasis
anything was fair game. I also had a number of virus questions that I knew going in that I was going to be screwed on b/c that minutiae was really better served by me studying other subjects.
3) Path/Pathophys & Phys: USMLE is loaded w/ path & pathophys questions that require a ton of thinking. EVERY question on pathophys of straight phys was 3rd or 4th order, but thats part of the beauty of the exam that makes it better than the COMLEX. My COMLEX had tons of 1st & 2nd order questions where you either knew the answer or you didnt (this is true for all sections.
4) Pharm: Tons & tons of pharm on the COMLEX (as expected). My test was very heavy in the following areas: Abx (huge!!), cardio, renal. Fairly straight-forward questions, but there were some really specific ones such as the specific Abx for an anaerobic sinus infection (I think they were basically asking this to see if you knew that Clindamycin is for anaerobes above the diaphragm, but
). USMLE had much less pharm, but I did have a significant amount of CNS & psych drugs.
5) OMM: I had a ridiculous amount of sacrum questions on my exam which is fine b/c they were relatively easy. Only 1 thoracic question & maybe 2 voodoo...I mean cranial questions & one was a WTF question that I couldnt find the answer to even by looking through all the books & notes I have & available on the internet. I only spent ½ day preparing for this, but was more than prepared b/c the great OMM department @ DMU.
6) Overall: USMLE was a much better (harder, but better) test. Question stems were long but you could reason out & think through >85% of the questions. USMLE is a very fair & well written exam, although I have no idea how well I did on it. COMLEX questions were shorter & you either knew the answer almost immediately or you did not (b/c of this I finished the exam nearly 1 hr early). I was disappointed in how little opportunity to reason through questions there was on the COMLEX.
I didnt hit on a few subjects, but if anyone wants to hear any other specific section comparisons, I would be happy to post my thoughts on those later.