Following questions were asked last time in interviews. I hope this would help in giving direction for preparation or at least minimize the anxiety Best of Luck boys and don't forget to share if you got something related to interview

Introduce yourself
Academic Qualifications
What are you doing these days
How you spend your free time
Why do you want to join NAB
Tell an incidence when you have to solve a problem between two parties
Computer Skills
What do you know about NAB
What are white collar crimes and blue collar crimes
Why do you want to leave your current organization
Are you flexible in your decisions or rigid
Can you manage pressure? Personal threats
Causes of corruption and remedies
What traits you value most in your life
Some questions from current affairs
Why to prefer fresh over experienced
Why you want to change your profession
Difference between investigation and inquiry
Why we should select you
greed based corruption is equally bad
Motivational factors
Moral ethics
Difference between civil and criminal law
How NAB is superior as compared to other investigation agencies
Maintaining good relations with your colleagues.
Political situation in Pakistan
International power shift
clash of civilization
Iran Israel conflict
moral decay in Pakistan
What do you know about Arab Spring
What is Judicial Activism
Something challenging that you have done in life
Question regarding current job