52 Weeks of Genealogy - Week 15 - Civil Registration and Certificates

We are now up to Week 15 of Shauna Hicks's 52 Weeks of Genealogical Records, and I am finally catching up.  Of course, this means I need to go back and fill in the first few topics I missed because I started late! 
Introducing the topic, Shauna tells us that the introduction of civil registration of births, deaths and marriages was a real plus for family history as certificates can give us those vital clues for moving back through the generations. Of course dates when registration was introduced and standard information on certificates varies from country to country but we really cannot confirm our research without these documents.
Birth certificates give us information on the parents and where they were from, marriage certificates also give us information on the parents and death certificates are particularly useful for telling us how long someone was in the colony or state if they an immigrant. 
Unfortunately certificates vary in detail and authority, especially death certificates.  Birth and marriage certificates are usually more reliable as the information they contain was supplied by the people concerned (although if they had something to hide they may have stretched the truth), but who supplied the information you find on a death certificate??  Having recently lost my father, I was the family member who filled in many of the details about his life (I'm fairly certain I got it all correct).  This got me thinking about who may have supplied the information on the older death certificates I have - the only thing you can be certain of is that it was not the person most concerned!  Was the informant their spouse, their sibling, their child?  Or an officiating doctor who had never met the deceased before assisted by nosy Mabel from across the road?  I have a few very disappointing death certificates with little or no information about the person's background, and one I know for certain contains totally incorrect information, which sent me off on quite a wild goose chase.
The cost of certificates can be expensive but digital images are often cheaper so make sure you look at what options are available.  Don't let the cost deter you from a valuable potential source of information.
If you have a brick wall then certificates may be very useful. Try looking at certificates for siblings if you cannot track a direct ancestor.  Find names of children on a death certificate.  Check the witnesses on a marriage certificate as they may be family members - if not parents then aunts and uncles, cousins, siblings.  Check if timelines and places fit with known family movements, see if occupations follow through families and generations. 
Thanks Shauna - this week's topic has sent me back to look at some of my certificates again to see if there is any details I have missed.