I lied. This is really about forbidden abbreviations. But I will do anything for more readers. (No, not really anything....)
One safety improvement I have learned about during the past several of years was the effort to prohibit certain medical abbreviations. This is a Joint Commission requirement, and it is a really, really good one.
For those of you non-medical folks out there, let me provide some examples relating to medication dosages. Now, you have to imagine these things being written in a doctor's handwriting to get the whole point. (Admittedly, this is corrected with computerized order entry, but that still does not exist everywhere.)
Trailing zeros. If you write a dosage that is supposed to be in whole units like this -- 1.0 mg -- it will often be read as "10 mg". That is a big difference, an entire order of magnitude. So the rule is "don't use terminal zeros for doses expressed in whole units." So it is properly done like this -- 1 mg.
Missing leading zeros. In contrast, when a dosage is a fractional amount, it is unacceptable to leave off the zero, like this -- .5 mg -- because it is easy for the decimal not to be seen and the dosage read as "5 mg", another order of magnitude problem. So the rule is to always use a preceding zero when the dose is less than a whole unit -- 0.5 mg.
You have to use some imagination for these next two, but remember, some people have really bad handwriting! An international unit was often called an IU. With bad handwriting, this could be read as "IV" (intravenous) or "10" (ten). The solution: Write out "international unit." Ditto for unit, or U, which could be mistaken for 0 (zero); 4 (four); or cc (cubic centimeter). So, it is now written out as "unit".
For frequency of medication, the old QOD, every other day, is gone. The "O" can be confused with a period, as in Q.D (once per day). What's the new terminology? -- "every other day."
When these requirements were first introduced, there was substantial resistance from some in the profession. That is pretty much past now, as people have become retrained, but there is occasional backsliding. I hope the medical schools are teaching the new rules so we don't have to retrain all those interns!