> ## Documentation Index
> Fetch the complete documentation index at: https://docs.pollandroll.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Sample sources

> Declare where respondents come from and manage multi-source fieldwork.

A sample source declares where your respondents come from: a panel, a contact file or social networks. Each sample source has its own URL and its own fieldwork progress. A survey can combine several sample sources.

## Create a sample source

<Steps>
  <Step title="Open the Sample source tab">
    Go to the **Sample source** tab in data collection.
  </Step>

  <Step title="One sample source per origin">
    Create one sample source per respondent origin. The simplest approach: one sample source per type of panel or per data source.
  </Step>

  <Step title="Set the provider">
    Set the provider: **Consumer panel**, **Own contact file** or **Social networks**. For a contact file, invitations are sent from the [E-mailing](/en/collecte/emailing) page.
  </Step>

  <Step title="Set the sample size">
    Enter the sample size you are targeting for this sample source (e.g. 200 interviews).
  </Step>

  <Step title="Panelist ID is required">
    State whether a panelist ID is needed. This ID links each respondent to their panel or, for a survey run on a contact file, to their entry in that file. On a panel survey, it can be passed back through the redirection URL, as a parameter of the link (see [Redirections](/en/collecte/redirections)). It also governs how duplicate responses are blocked (see below).
  </Step>
</Steps>

<Tip>
  Example of fieldwork with three sample sources: a **Consumer panel** source, a source for a **boost on Meta** (or a part of the sample collected on Meta) and an **Own contact file** source (a brand's customer base). Each one is created, launched and followed separately.
</Tip>

## Avoid duplicate responses

The panelist ID is what allows poll\&roll to recognize the same person from one visit to the next. The **Panelist ID is required** setting therefore directly changes the level of protection against multiple responses:

| Panelist ID is required | What is blocked |
| - | - |
| **Yes** | A given respondent can only answer once, whatever device they use. |
| **No** | A given respondent is only blocked on **the same device**. If they use several devices (phone then computer, for example), they could answer several times. |

<Note>
  A panelist ID must not contain `?` or `/`. A link that appends a path or an extra parameter after its value produces an invalid ID, and the interview is not created.
</Note>

Make the ID required as soon as you have an ID available in your sample source. Leaving it optional is justified when there is no ID to pass on — a **Social networks** source, or in some cases an **Own contact file**. It also applies when a generic link, identical for every respondent, is required.

## Rename a sample source

You can rename each sample source to tell them apart, for example an internal panel and an external panel.

## Combine several sample sources

On multi-source fieldwork, each sample source generates a **separate URL** (retrieved in the [Launch](/en/collecte/lancement) tab) and **separate progress monitoring**: completes, screen outs and incidence per sample source. You can therefore steer each sample source independently and fine-tune fieldwork for each of them (chase a lagging panel, slow down a source that is running ahead, and so on).

From the moment you create them, anticipate the distinctions you will need at the analysis stage: this is the right time to plan how you will want to separate your targets and your different launches.

<Note>
  The sample source does not appear in the results, but it is present in the [interview list](/en/collecte/liste-des-interviews). You can therefore recreate a "sample source" variable to crosstab it at the analysis stage (e.g. to tell a panel send apart from a boost on social networks).
</Note>


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