4 ms·
I've found even glucose meters to be wildly inaccurate. There is often a 20% difference in readings between two meters moments apart, and thats enough to have c
by moultano 11y ago
I've found even glucose meters to be wildly inaccurate. There is often a 20% difference in readings between two meters moments apart, and thats enough to have consequences for how your care is managed.
- RA_Fisher 11y agoIt's pretty heteroskedastic, which practically makes the errors not tooo bad. For example, say my wife is low (< 70), in that case the error rate will be small. That's where precision matters. Now suppose she's 200+, in that case the errors will be large but it doesn't really impact how to take care of it. In terms of error, What worries me much more is a server at a restaurant giving my wife a regular coke rather than a diet coke or vice versa. Where smaller blood is really beneficial is that it requires a less painful finger prick.
- Fede_V 11y agoIf the error is proportional to the measurement - can't you just take the log to make it additive again?
- RA_Fisher 11y agoHmm, it's not clear to me what the benefit of that would be in terms of information (a transformation). It's univariate data, it's been a bit since I looked at it but a histogram showed readings were lognormal / weibull / gamma distributed (point is asymmetric, right-skewed), I believe. In terms of inference, it's kind of mind-bending to think of a "population" of blood and each person having a specific variation.
- jonlucc 11y agoI've noticed this as well in rodents. Take 2 consecutive drops and the readings can be as much as 60 mg/dl off. It's not a problem for us because we take duplicate measures, and if they are too far off, we can remeasure. An individual with one meter and only one drop must be relying very heavily on a pretty inaccurate measurement.