I just took my test last week and passed with 70 questions. I read my entire textbook, and maybe more importantly, I took many free practice tests found online, and I also paid for online test prep questions. I answered over 1000 questions taking various practice tests, and scored from about 77% to 94%.
The NREMT questions were fairly basic, although many of them were scenario-based, so read each question carefully. I saw many questions specifically on the following topics:
Know your vitals backwards and forward. Know the acceptable ranges of BP, pulse, and respirations for adults and peds.
Know CPR as if your life depends on it. Probably 25-30% of my test questons were on CPR/compression ratios/assisted ventilation rates/tidal volume.
Live and breathe OPQRST/SAMPLE/AVPU.
Know definitions of distal/medial/proximal/midaxillary etc.
Understand how carbon monoxide affects the O2 sat monitor.
Understand the correct steps to open an airway.
Know steps for C-spine.
Understand OPA vs NPA, ie how to measure/contraindications.
Know how to triage based on a given scenario (VITALS.)
Know transport positions based on signs/symptoms. Know your obstetrics as it relates to C-spine.
Know layers of skin and burn classifications.
Know lung sounds, upper vs lower.
Know stroke signs.
Know early and late stages of shock.
Know definition of good perfusion, physiology of how the body exchanges carbon dioxide for oxygen, and blood facts such as how much blood do adults generally have and how much loss constitutes a dire situation.
You may see a handful of questions on safe driving and some on proper use of the radio.
I did not see a single question on high altitude sickness, GCS scores, burn percentages, APGAR, basic anatomy, or the two methods of determing strokes. With that being said, however, you would be wise to know all of those areas. My ride alongs with ambulance and FD's are big on GCS scores for example.