Which are the best institutions for...?

Which are the best institutions out there where a nurse can obtain certification in: a. Case Management? b: Legal Nurse Consulting? c: Nurse Management? d: Forensic Nursing? e: Nurse Informatics?

The nature of this question leads me to believe you do not have much experience as a nurse.

If I am correct, you would be wasting your time and money pursuing an education program for any of these. Nursing experience would be the best pathway to any of these specialties.

Recognized specialty certifications are from "nationally recognized" organizations - not those whose main business is 'selling' educational programs. The primary organization in the US is the ANCC ANCC Certification Center . Other valid certifications are from non-profit specialty organizations such as AACN and ANPD. In each case, certification is bestowed upon successful completion of a comprehensive examination - & there are very specific criteria that must be met in order to qualify for the examination.

The certifications you mention all require at least a year, or more (some, much more) doing the job to even sit for the exam. The CCM alone requires a 4-year degree. The LNCC requires years of experience.

I suggest you take the time to look up each of those certifications and then finish up your homework assignment by making a table of the requirements and time required. While you're at it, look for the difference between a certificate and a certification. It is a significant difference.