How to find the day of the week

[gani davlatyov]

Hi everyone,
I have a clinical intervention data with adverse events. I want to see if adverse events are more likely to be reported during specific months (season), and/or days of the week. So, I need to create two categorical variables: one for the weekdays and the other for the month.
Thank you.

Here is the data:

* Example generated by -dataex-. To install: ssc install dataex
clear
input int ID str10 adverse_event_date
 1 "2019-01-30"
 2 "2018-03-24"
 3 "2018-03-22"
 4 "2018-10-25"
 5 "2018-07-19"
 6 "2018-04-03"
 7 "2018-12-12"
 8 "2018-09-04"
 9 "2019-01-30"
10 "2019-01-30"
11 "2018-12-10"
12 "2018-08-15"
13 "2018-07-20"
14 "2018-11-05"
15 "2018-12-12"
16 "2018-07-03"
17 "2018-12-11"
end

[Joseph Coveney]

help datetime

Then search in the pop-up window for "calendar month" and then "dow". It will show you the relevant functions to get this information. (Be sure to convert your string date into an "SIF" date first. The function for that's there, too.)

[Attaullah Shah]

* Convert string date to Stata date
gen daily_date = date(adverse_event_date , "YMD")
format daily_date %td

* Weeks of the year
gen weekly_date = week(daily_date)

*create monthly date
gen monthly_date = month(daily_date)

* Week days
gen week_days = dow(daily_date )
*Description: the numeric day of the week corresponding to date e d; 0 = Sunday, 1 = Monday,. . . , 6 = Saturday

[gani davlatyov]

Thank you for your help.