The death info has been cobbled together from multiple sources.
Generally speaking, any source I have used (for the entire project) is
listed in the "references and acknowledgements" part of the readme
file included with each release. The death information specifically
has generally come from one of the following:

- Total Hockey
- hockey-reference.com
- Find A Grave (www.findagrave.com)
- SIHR (www.sihrhockey.org) - they've posted annual lists of
hockey-related deaths for the last several years
- LostHockey.com (www.losthockey.com)

I have occasionally added recent deaths (the last year or so) after
seeing news stories on ESPN.com, the hockhist Yahoo group, HFBoards,
etc. Though of course, these generally show up in the annual SIHR
lists. In case you're wondering, as a general rule I avoid using
Wikipedia for anything that I can't corroborate elsewhere.

As far as reliability of the information is concerned, I'm fairly
confident the death info is fairly reliable. However, keep in mind
that consulting multiple sources will sometimes yield different dates
for the same player. There's also one case in particular that's
probably wrong. There are two players in the database named Jack
McDonald - one born in 1887, the other in 1921. Total Hockey and
Hockey-reference.com give a date of death for *both* as 1/24/58. Two
players with the same name, born 34 years apart, both dying on the
same date? Seems like an incredible coincidence (though Adams and
Jefferson both died on the 50th anniversary of the Declaration of
Independence, so I suppose anything is possible) - I suspect the
likely explanation is a mixup given the identical names.

The "9999" entries indicate that a player is known to be deceased, but
no specific details are known. I have only marked players as deceased
in this way if they are indicated as such either in Total Hockey, or
in the player career totals lists in the Official NHL Guide & Record
Book. There are a number of other players who can be presumed to be
deceased given their birth year, but I have not marked them as
deceased without confirmation.

Doug

--- In hockey-databank@yahoogroups.com, "chris.fletcher66"
<cfmletcher@...> wrote:
>
> Hi - This is a great resource, thanks for putting it together! I am
starting a bit of research on
> how long hockey players live, change in lifespan over time, and
comparisons to the national
> (canada) average.
>
> A couple of questions about the database:
>
> Where do date of death records come from? I am curious about how
much confidence we can
> put in these dates.
>
> Some DoD fields are marked "9999" and others are blank including
people born in the 1890s
> and presumably gone now. Is there a distinction here?
>
> Cheers,
>
> Chris Fletcher
>