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NTP is great and all, but...

When you're timing something that needs accuracy, you use a timer not a clock. If you need to use a clock, you use one clock not all the clocks. Yes, I work in the medical industry. Yes, we generally use timers not clocks. Yes, our clocks are all wrong too.

If you really do need a solution to the "time" problem (accurate time all the time), you need to issue everyone a smartphone.



im a doctor also and the need for highly accurate timing is exceedingly rare.

A lot of medical timing is guess work - why are antibiotics commonly prescribed for 5, 7, 10 or 14 days? Whynot 6?

Automatic filing of EMR information would be important and the legal aspect would unfortunately demanc the greatest amount of accuracy.

Surely connected devices could use one centrally calculated timesource?


> "Surely connected devices could use one centrally calculated timesource?"

... like NTP?

Sorry, but I'm not sure what point you are trying to make here. Anything with a computer, even a microcontroller, and basic network connectivity can use NTP, it is an extremely simple protocol.

Anything that doesn't connect to a network could be kept in sync via a wireless pulse/tick, though then you have security issues unless you cryptographically sign the clock signal. Though I'm not sure why anybody would try and screw up a clock signal like that other than general asshattedness.

That aside, I'm unsure why they are using local time for logging data anyhow. If the folks managing the hospital were rational, shouldn't there be a regulation to use GMT and 24-hour clock? My home town is right on the Eastern/Central timezone split, and I know it causes all kinds of problems in day-to-day life. I just hate that kind of ambiguity.


> If the folks managing the hospital were rational, shouldn't there be a regulation to use GMT and 24-hour clock?

People are not rational, that's the problem! Just look at any web app that can't get timezones right.

In addition, most Americans swear by EST, CST, PST, etc. and have no idea how many hours behind GMT they are. Record everything in GMT and soon there will be a similar article documenting how medical professionals routinely misinterpret GMT timestamps. Especially in March and November.


When lives are at stake, people tend to be more amenable to changes like GMT and 24-hour clock. If the military can do it, a civilian organization with sufficient motivation (insurance terms, regulation, etc) should be able to make the same shift.

However, I was referring more toward the recording system than the staff. If the recording systems were all using unix time stamp with a GMT system clock synchronized over NTP, there would be no ambiguity as to when a record was added to the system. End user systems could be responsible for keeping track of what time zone the user is in, and could convert as necessary. The important thing is that the "One True Datum" have the appropriate stamp.


> End user systems could be responsible for keeping track of what time zone the user is in, and could convert as necessary.

That would require routine updates to the timezone database, which is a bit more complicated than NTP. (Yes, DST rules change all the time. The U.S. changed its rules just a few years ago.)

Hopefully, the rise of cheap and powerful ARM SoCs will make it impossible for device manufacturers to make excuses about not running a proper OS on their machines anymore. I would love to see more Linux and BSD on medical devices.


Except that my iphone is usually off by a few minutes. I don't think Apple got their NTP implementation or usage quite right.


Most mobile phones usually get their time from the phone towers. Of course, this relies on them having the right time.

Interestingly the most effective way to get syncronised clocks is GPS.


I'm pretty sure cell towers all use gps for time synchronization, which is necessary for the network to work.

I always trust my cell phone time.


Cell towers need synchronized clocks? For what?


I'm pretty certain that CDMA towers, at least, had exceptionally accurate clocks for something related to the technology (synchronizing the chip code maybe? it's a guess).

Not sure if this applies to GSM as well, but CDMA used to be an acceptable clock source for a Statum 0 clock source.


You technically don't even need accurate time, you need consistent time. If all your clocks are consistently slow by 10 minutes, there's less of an issue then if some of the clocks are slow by 10 minutes.




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