The frequency indicates the number of dose moments per time unit, usually per day. If this frequency is included, then the Interval will not have been included. Usually, frequency comprises both amount and time unit (3 times a day), but it can occur without the time unit (single use). In that case, a reasonable distribution over the day is expected, but exact times are not given. This is left to the patient. It is the most common manner of extramural prescription. In the case of Baxter packs and intramural care, such a prescription is used to draw up a (location-specific) outline for distribution times (logistics). The time unit of the frequency must be the same as how it is indicated in the textual description of the dose. Example: for a '2x a day...' dose: amount = 2 time unit = 'day'. for a '3x a week...' dose: amount = 3 time unit = 'week'.