Assuming even distribution and not considering time changes/DST, the difference between recorded time and the actual time of birth will be at most 12 hours if you use noon, but up to 24 hours if you use midnight (born at 23:59, but recorded as 00:00). That would make the average difference (again, assuming even distribution) 6 hours for noon, but 12 hours for midnight.
On 2020-01-09 14:39, Paul Eggert wrote:
> On 1/9/20 6:15 AM, Andrew Lyon wrote:
>> if the hour of birth is unknown (for patients born 1930-41), that a birth hour
>> of midnight is assigned as a default.
>
> If the birth hour is unknown you might be better off defaulting to noon than to
> midnight. First, noon is likely closer to the actual birth hour.[1] Second,
> you'll avoid some of these software glitches.
>
> [1] https://www.cdc.gov/nchs/products/databriefs/db200.htm
That may be true for the 41 states of the US sampled, where most births are
likely to be in hospitals, records may be accurate, and births may be induced to
occur when staff are available, indicated by the reports of peak periods; however:
"Noninduced vaginal deliveries had the most even distribution across the hours
of the day, fluctuating close to the average of 4.2%."
The other 9 states may be more rural and the distribution more even.
In the rest of the world, where doctors, midwives, or families are likely to
have to deal with births as and when they happen, a random time of day will be
as accurate.
However, dealing with noon (or 0400-2200) local time means you should never have
to worry about changes.
--
Take care. Thanks, Brian Inglis, Calgary, Alberta, Canada
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