EVOLUTION Values and Dates

The information to generate an evolution graph (case_evolution_graph()) or to retrieve evolution data (https://linkcare.atlassian.net/wiki/spaces/DES/pages/2574516249) is obtained from ITEMs that have assigned a specific DATA_CODE.

For example, when we want to display a graph of the ‘HR’ DATACODE (Heart Rate) in a certain date range, the API will search all the ITEMS with that specific DATACODE in the desired date range.

By default, the date assigned to each value represented is the date/time of the TASK where the DATACODE was located.

In the following example the have 3 TASKs where each TASK contains a Heart Rate value

Where the API assumes that the date associated to HR values 76, 82, 79 is respectively 2020-06-23 11:33:25, 2020-06-24 12:21:31 and 2020-06-25 09:15:16.

Specifying a different time

Nevertheless, sometimes it is desirable to assign a different time than the TASK time (specially if you take into account that the TASK time is the time when that TASK is closed, but the value could be collected at a different time). Or maybe we want to store multiple values in a single TASK, where each value corresponds to a different time.

For example, consider a TASK to record the physical activity of a patient where we want to record the steps walked at different times of the day. In this situation it would be quite annoying to have a multiple TASKs in the same day just to record the number of steps walked in different time intervals. It would be much better to have a single TASK with all the values.

To solve this problem, there exists a mechanism to assign a time different than the TASK time to each value. The way to do this is to append an special ITEM in the FORM with DATACODE = ‘#EVOLUTION_TIME’. If this ITEM exists, then the values represented in the graph that belong to the same FORM will adopt the date of the TASK and the time specified in the ‘#EVOLUTION_TIME’ ITEM.

It is also supported to have an array of ITEMS in a FORM, in which case each value of the evolution data will use the corresponding time stored in the ‘#EVOLUTION_TIME’ ITEM of the same row.

In the following example we have a TASK with an array of ITEMS recording the number of steps walked by a patient at different intervals of the day:

In this situation the evolution values would be 2235, 3245, 3555 and the respective times would be 2021-06-01 09:00, 2021-06-01 10:00 and 2021-06-01 11:00