I am indexing Ontario Birth records right now and apparently we are reveiwing another sites index for these records. I find it interesting how the previous indexer assumed certain things.
Like the registration year as being the same as the birth year. There have been some families that when they register a birth, they register the previous one or two births at the same time. The difference in registration year and actual birth year can be important. My grandpa Johnny Bionaz was born in 1904, but the birth registry says 1905. When you look at the page in the registry and the date of registration you realize the register wrote down the wrong year. The birth is given as 21 Oct 1905, but was registered in May 1905. the register was just used to writing 1905 that he did not catch the late registration.
Also how the previous indexer applied today's last names to these records. It was common back then to use the mother's surname as part of the child's middle name. Well the previous indexer assumed that the child's surname was a combination of both parents surname and indexed it as such.
Also, I have research that was compiled a long time ago that has problems with dates and Counties. The problem with the dates is the researcher used the New Calendar when transcribing Old Calender dates, thus putting the months wrong. The problem with the counties is that Counties can change and some of the records contain the old county and some contain the new county and yet the town and state are the same.
We need to remember as we work on our Genealogy that times have changed and that we need to record or at least note the original otherwise it may confuse someone else. And that someone else might actually be ourselves.