meanmediannotation
I usually use mean±SD notation for reporting values. I know that many people use mean (SD) notation and I understand why.
Right now in the document I am writing I am also reporting medians but I don't know which notation I should use for the 3 measures. Any suggestions?
You can report a confidence interval for the median. In R, you can use wilcox.test with the argument conf.int=TRUE. There's a tiny discussion of this in John Verzani's simpleR notes: see here.
Regarding plots: I don't really like using bar plots even for representing a set of means. I'd prefer to just plot little line segments for the CI:
The plot on the right was made with errbar() from the Hmisc package [CRAN page].
You could make the same sort of plot for the medians and the related confidence intervals, or you could use box plots (which, in the same amount of space, describe the entire distribution).
It is good practice to report some measure of variability with any result. It does not really matter whether you report the standard deviation, the standard error, a confidence interval as the reader can convert between them as long as s/he knows the sample size. You do not say exactly which field of science you work in but there is probably a convention which it is best to follow so as not to annoy the reader.
Best Answer
Both conventions you mention are ambiguous - for example you can't tell whether the number after the $\pm$ is a standard deviation, a standard error, or the half-width of an interval. (a problem that has led to numerous questions on this site).
If you're publishing somewhere that offers precise guidelines follow those, but otherwise I suggest being explicit, for example: $``\text{median } 28.5,$ $\text{ mean } 31.2,$ $\text{ standard deviation } 3.6\!"$ -- then there's no possibility of misinterpretation.