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Select Edit Mode in the top right corner
The questions reappear in an editable format
Press Actions (formerly Edit) next to the question you wish to edit
A popup appears that lets you edit the question
The Outcome field shows the outcome that the question will now be assigned to. (If your organisation has not yet created its own outcome, it might display your organisation’s automatically-generated 1st outcome)
Given that every quantitative survey question (i.e. Multiple Choice, Numerical or Achievement) is saved in your account as a Progress Tracker which can be used on multiple surveys, when you edit the survey in this way you are prompted to choose whether you want to
Apply this change to only this survey (i.e. this will in effect create a new Progress Tracker and remove the old one from this survey; in so doing, it will remove previous answers to this question)
Apply this change to all surveys and all projects that use this Progress Tracker (this will not remove previous answers to this question)
Press Save
The popup closes
Untick the Edit Mode checkbox to return to the normal mode.
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You can edit the Survey Question Wording and/or Name of the Metric from the Edit Question popup on the Survey page using the Edit Mode.
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You can apply the edits made to the metric in one of the two places
Only on the survey (creates a new question)
Everywhere (on all surveys that use this metric)
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Summary
You can extend a single choice field on a survey and expand the answer choices available. This can be done after you have initially created, published and made the survey.