To edit a previous entry made to a Lab Test;
1) Go into the relevant lab test that you want to update a reading for.
2) Select the 'History' button on the top right of the lab test entry page.
3) Select or browse to the date (using the date selection tool) that you want to update.
4) Click the date label and you will see the lab test page that reflects the data that you entered on that day and time.
5) Update the entry and select the 'Save' button. Your reading will now have been updated.