days since (also weeks, months, years)

days since calculates the number of days since a particular episode. Similarly for weeks, months, years.

For example, given the following case fragment,

           01 Jun 03    20 Jun 03    30 Jun 03    15 Oct 03    02 Nov 03
HDL           2.0          2.1          2.2          2.5          1.9
LDL                        6.2*         5.0*                      3.9
Trig          3.6                                    3.6
LipidDrug     N                         Y            Y

at least 15 days since most recent Trig where Trig is available

more than 2 weeks since second most recent HDL

more than 3 months since most recent high LDL

less than 1 month since second most recent HDL Note the singular: ‘month’.

less than 1 year since ( most recent ( Trig > 2.0 ) )

less than 1 year since max LDL

less than 6 months since ( ( most recent ( high LDL ) ) where ( LipidDrug is “Y” ) )

at least 150 days since first Notes