I'm not sure if I fully understand the part about "turn gray in the calendar"
If you are using a survey to collect participant appointment date, I would recommend looking into using the @MAXCHOICE action tag to limit the number of times participants can select a value in a radio/dropdown field.
Add each date/time as an option and set a @MAXCHOICE action tag to only allow that specific timeslot to be selected once.
I meant the date will be unavailable by " turning gray". That is a good logic indeed but I have 8 months of data collection planned ahead so that makes MAXCHOICE unfitting :(
Thank you for the recommendations tho!
Don't use a text field with datetime validation for this.
Use a drop-down field with the slots as options and a MAXCHOICE action tag per u/obnoxiouscarbuncle suggestions
I'm not sure if I fully understand the part about "turn gray in the calendar" If you are using a survey to collect participant appointment date, I would recommend looking into using the @MAXCHOICE action tag to limit the number of times participants can select a value in a radio/dropdown field. Add each date/time as an option and set a @MAXCHOICE action tag to only allow that specific timeslot to be selected once.
I meant the date will be unavailable by " turning gray". That is a good logic indeed but I have 8 months of data collection planned ahead so that makes MAXCHOICE unfitting :( Thank you for the recommendations tho!
Unless there is some external module I am unaware of I really don't think REDCap has this type of functionality to look across records.
Don't use a text field with datetime validation for this. Use a drop-down field with the slots as options and a MAXCHOICE action tag per u/obnoxiouscarbuncle suggestions