Medical Examiner Dr. Qin

-The male lead in both dramas are cold and experienced in their line of work.
- The female lead is a newbie or in case of Dr. Frost a student.
- They are not investigators but they help the police.
- Dr. Frost focuses on the psychological aspect while Dr. Qin leans towards the forensics
- The main plot of the story focuses on the life of the main leads and they both have dark pasts.
- Both dramas have interesting crimes :)

- The male leads have a dark past and the main plot revolves around them.
- The female leads are both their juniors who joins the team.
- Both series focuses on homicide cases

Both are crime solving dramas involving a great cast. however the main leads in Dr.Qin don't have any romance; its just friendship but the chemistry for friendship was there. I thoroughly enjoyed both although Dr.Qin is a bit more gruesome and involves more medical aspects

Both dramas shows the use of forensic pathology to solve crimes and catch the killer. While unnatural death solely focuses on the forensic part, Dr Qin includes police work too.
Both have excellent female leads but Dr Qin is more graphical.

Although both the dramas are set in different time period, they are similar somehow in relation to the investigation and follow-up examination. My roommate is a detective has elements of romance while the Medical Examiner Dr.Qin has very little or almost no romance (from what I recall).