How are Civilian casualties estimated/counted?

[Marquise]

Him forum.
I have a fair knowledge of how Military cas. are counted/estimated, but I wonder about the civilian ones. How is it done?
To help you give an answer. I'll elaborate on what kind of info I am looking for:
1) How are Civilian casualties estimated/counted? (methods used)
2) Are the numbers broken down into categories like the military ones? (Killed, missing, etc)
3) Are there gender or age-related categories of civilian casualties? (elderly, childre, women, men)
4) Are the circunstances of death/dissappearance differentiated, or are all victims thrown into one lot? ( I mean, is there a different method for estimating/counting unintentional cas., as in caught in crossfire between factions, and intentional cas., as in reprisals, murder, retaliation against partisans, etc.)
5.- Are partisans included as civilian cas., or is there a separate category for them?

Thanks in advance for any information regrading this subject. And please, don't include victims of the Holocaust,or murdered by the Einsatzgruppen or KL inmates., only those civilians living in cities, towns, farms or the country, if you get my point.