Ethical Consideration:
1-Ethical approval was taken from Department Of Community Medicine, University Of Khartoum, and the research was conducted after approval from my supervisor.
2-Volunterism (each individual was voluntarily participating).
3-Each individual was having the right of withdrawal at any time of the study.
4-The researcher was committed of doing no harm.
5-Consent was obtained in a written way and brief introduction was given before taking the information from the candidates.
6-High degree of confidentiality was preserved.