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For setting up '0' days or an empty value, OpenSpecimen hides pending specimen immediately after immediately after collection of the visit.
If the user wants to show pending specimens all the time, the user needs to set some bigger more significant value in "Pending Specimens Display Interval" like 36525 36525 days (i.e., hide after 100 years).
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From the Visits page, you can hide/unhide such pending specimens using the More->Show Pending option.
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