Hello,
I am looking to understand when each subject took their medication in order to see how much time has passed since medication intake during the completion of the tasks. I am specifically looking at days 1 and 4 when the subjects were in clinic .
A. It is not clear to me when the subjects took the medication during day 1. In the onboarding table it says "last_levodopa_dose_timestamp" but it seems to be shifted in time. Am I supposed to subtract the timezone differences ?
For example, subject 7_NYC
last_levodopa_dose_timestamp = Mon Apr 13 2015 16:20:00 GMT+0000
recording_start (from onboarding table) = 11:34:00
recording_end (from onboarding table) = 14:54:00
timestamp_start (of first task session1 of the subject from the Task_Scores_Part_1 table) = Mon Apr 13 2015 12:44:26 GMT+0000
timestamp_end (of last task session7 of the subject from the Task_Scores_Part_1 table) = Mon Apr 13 2015 15:57:26 GMT+0000
Is the levodopa dose supposed to be 12:20:00 GMT as the subject is in timezone GMT-4 ? Then the subject would be taking the medication right before the start of the battery of tasks.
B. Do we have information on the time of day the subject took levodopa the morning of entering the clinic ? For purposes of understanding how much time has passed since Levodopa intake during the performance of the UPDRS segment?
C. Finally, the recording _end variable is not clear to me as the last task in the battery of tasks was not finished until 15:57:26.
Created by Tanya Dimitrov tanyadimitrov * Timestamps are in standard Unix Time format (Unix time is a system for describing a point in time. It is the number of seconds that have elapsed since the Unix epoch, excluding leap seconds. The Unix epoch is 00:00:00 UTC on 1 January 1970).
* The sources of medication information available are `Metadata of Patient Onboarding` (last_levodopa_dose_timestamp), `Metadata of Laboratory Visits`, `Medication Diary`, and `UPDRS Responses` (item 3C.1). Thank you @sieberts for your reply.
About question A, I wanted to confirm that the excels are not all formatted in the same timezone for each patient. In the example I gave above, the last_levodopa_dose variable seems to be in the patient's own timezone, but the other timestamps such as timestamp_start (Task_Scores_Part_1 table) ) seem to be in GMT.
A+B, the last_levodopa_dose here is AFTER the UPDRS segment was performed in clinic. Do we have information about what time the patient took the medication BEFORE coming into clinic?
A. You can convert Unix timestamps to any timezone you prefer to work in. The local timezone is listed in the `Metadata of Patient Visits` table. For visit 1, patients are supposed to start the battery in the "on" state, so it is possible they took meds shortly before the start of activities.
B. For visit 1, the last dose is listed in the `Metadata of Patient Onboarding` table. For visit 2, the medication data can be found in the `Medication Diary`.
C. It is possible that the clock used to record this variable was not set correctly. You may have to infer the conversion here.