There has been many speculations especially on this thread:
https://www.nairaland.com/5255981/why-doctors-start-federal-job

Upon my indepth research, i discovered logically it is not true except one doesn't understand logic behind salary structure. Engineers and Doctors start from the same level mathematically. People comparing the two professions together are comparing: Fresh Registered Doctor (with MBBS + 1yr housemanship + Nysc) with Fresh unregistered Engineer(with B eng + Nysc):

Registered Doctor (at least before you are free to practice): 6yrs mbbs + 1yr (housmanship) + 1yr (NYSC) = 8yrs (before you can be employed by hospital). Note: Some might not get housemanship placement in one yr because of limited numbers of hospitals availability. So, for a fully registered doctor to be employed after NYSC, about 8-10yrs must have been spent, it means:
After 8-10yrs as registered doctor fully ready to practise at Federal, the person will start at level 12

For engineer, a fresh graduate in engineering is not yet an engineer, except he is certified by relevant bodies in engineering before he/she can be fully ready to be called engineer:
engineering (B engr ): 5yrs + 1yr = 6yr (fresh graduate not yet registered engineer, but can begin work if he likes at level 9 in public service), two yrs after (8yrs-when doctor is doing housemanship if he is lucky to get housemanship on time), engineer in federal service already moved to level 10. At 9/10 yrs when doctor must have finished NYSC and qualified to work in any hospital as registered doctor (i.e federal), by this time, engineer already has 4yrs post-graduate experience and become registered engineer through coren(fresh registered engineer) who now starts at level 12 which is the same as that of doctor(registered). Engineer even gets better opportunity because many factors can cause medical doctor to be delayed than 8/9/10yrs and also, engineer has been collecting money even before becoming registered engineer while doctor was still paying money to school and other finances before becoming registered. Amount collected during 1yr housemanship can not be compared with what level 10 engineer has collected so far. So, people that structured federal salary scale know what they are doing, fresh registered doctor and fresh registered engineer in federal institutions are logically starting on the same level in public service, numbers of years play important role.

https://nse.org.ng/news-events/recent-news/entry-point-for-engineers

Are you a doctor sir/ma?
I will like to know you better.

I am a student.

sreamsense nice o