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Recruitment Policies

  • Recruitment Policies: Overview
  • Disabled
  • Crowdsource recruitment options:
  • Simple Link
  • Pilot
  • Supervised
  • Email recruitment options:
  • Email Shot
  • Email ID
  • Third party recruitment options:
  • 3rd Party
  • Prolific
  • Sona Systems®
  • Amazon Mechanical Turk
  • CloudResearch: Connect
  • CloudResearch: MTurk Toolkit
  • Qualtrics
  • Qualtrics Panel
  • Kantar Profiles
  • Custom 3rd Party Setup
  • Incentives for participants:
  • Reward Node

Recruitment Policies: Overview


Welcome to the Recruitment Policy Options Tooling Reference Guide!

Here, you can explore the different recruitment policies available in Gorilla by browsing the list on the left. Recruitment policies determine how you distribute the link to your experiment and vary based on how you recruit participants. Below, we outline the possible use cases for each recruitment policy:


Crowdsource recruitment options
Use the Crowdsource recruitment options if you're piloting, recruiting via social media, or running a study in person.

  • Simple Link: Use this policy when recruiting through social media but remember to include a Bot Check! This policy does not identify participants, so if they stop partway through the study, they cannot resume.
  • Pilot: Use this policy when piloting your study. This recruitment policy provides a link where participants must log in using a text string as their ID. The text string isn’t restricted, so participants can use any value to log in.
  • Supervised: Use this policy if you're running an experiment in person, for example in a classroom or a lab. You can provide a list of IDs, which participants will use to log in and access or resume the experiment.

Email recruitment options
If you already have a group of participants and their email addresses, you can use an Email based recruitment policy to send them your experiment.

  • Email Shot: Use this recruitment policy to participants send an email with a personalised link to access or resume the study.
  • Email ID: Use this recruitment policy to send participants an email with a generic link to the study and an ID for logging in to access or resume.

Third party recruitment options
If you plan to recruit participants through a 3rd Party Recruitment Service, we have integrated recruitment policies for some providers (see the list on the left). If your recruitment provider isn’t listed, you can use the Custom 3rd Party Setup.

Screenshot of all the third party recruitment services logos
Pro Tip

Want to run a longitudinal study? But not sure what recruitment policy to use?
Check out our Longitudinal or Multi-Part Studies guidance

Disabled


The recruitment policy is Disabled by default when you create a new experiment. You are able to preview and edit your task but participants are not able to access it via any of the previous methods. Once you have completed your data collection on an experiment, or if you need to halt the experiment for any reason, returning the recruitment policy to 'Disabled' again will prevent any further access, regardless of the previous recruitment policy setting.

Pilot


Anonymous Recruitment Policy
This is an anonymous recruitment policy, unless you explicitly collect identifying data or use identifying participant IDs

This recruitment policy provides a link where participants have to log in using a text string as an ID. This text string is not controlled, so they can log in with anything. If anonymous recruitment is important for your study, ensure your participants do not choose an identifying text string, or use a different recruitment policy.

We often use this policy for testing by using names like Test1, Test2, TestN! We also use it for piloting on team members, with us each using our initials.

Similar to the Simple link, the link can be distributed by any means. The additional benefit is the ability to identify participants later on, allow participants to resume where they left off.

Testing your experiment using the Pilot recruitment policy requires you to set a Recruitment Target and assign tokens to your experiment in the same way as all other recruitment policies. You can read some more information about piloting experiments in our From Creation to Launch guide.

Note: If the participant clicks on the link from within a mobile app, the experiment may open within the app, rather than in a full browser such as Safari or Chrome. If this occurs, participants may not be able to complete tasks. We strongly recommend you ask participants to copy and paste the link for use on mobiles, rather than clicking it.


Supervised


Anonymous Recruitment Policy
This is an anonymous recruitment policy, unless you explicitly collect identifying data such as email addresses or use identifying participant IDs

This recruitment policy allows you to define a set of Public IDs to be used with participants who will log in using a generic link. The Supervised policy is intended for use in a case where participants may not have email addresses and/or the experiment will take place in an area you can control/supervise such as a classroom or lab. Similarly to Email Shot, Email ID, and Pilot policies, participants would be able to log in and resume their experiment where they left it. If a participant shared their public ID with someone else, that person would be able to log in as them. However, using this method in a controlled area such as a classroom or lab limits the possibility that a user could utilise someone else's ID.

Resend Email Action: If you do decide to use this policy in an unsupervised area, you can send participants emails. From your participants screen (for participants you have uploaded emails for) you can select the 'resend email' from the Action-menu. This will send the participant an email reminder to take part in your experiment. You may also wish to use this action to encourage participants to continue with their experiment if they have not yet returned to complete it.

Note: You can add new participants to your experiment at any time: simply upload a new .csv, .xlsx, or .ods file with IDs you wish to add - these will be added to your list of IDs, without overwriting the existing ones. Once you have uploaded your IDs, the Status will show as Pending in your Participant tab. You must click Activate in the 'Activated' column (or Activate All on the top right) before your participants will be able to start your experiment. Once you have done this, the 'Status' and 'Activated' columns will show the participant as Activated until they start your experiment, as shown below:

The Participant tab shows your participants as Pending or Activated

Email Shot


Identifying Recruitment Policy
This is an identifying recruitment policy, as it requires participant email addresses

This recruitment policy allows you to define a list of email addresses and public IDs for participants. Unlike the Email ID policy (which uses a generic link), each email address receives a personalised link. This allows you to identify participants without them needing to log in with an ID, and prevents participants from repeating an experiment more than once. There is nothing to prevent the participant from sharing their unique URL with some else, though they will still only be able to complete the experiment once. Participants also have the option to complete part of the experiment and then continue later by using the URL again.



Customise email

You can customise the email you send to participants by selecting Customise Recruitment Email from your Recruitment tab settings as shown below:

A screenshot of the Recruitment Tab of the Experiment Builder. The Email Shot recruitment policy has been chosen, and the Settings button has been clicked to show the Customise Recruitment Email option.

Fill in the Subject and Body boxes with customised information you wish to display to your participants. Make sure you include the tag {{url}} in your email where you would like to place the recruitment link. You can also add in the participant's name (as it appears in your Participants tab) using the tag {{name}}. The email can be further customised via HTML formatting.

Resend email

From your Participants screen you can select 'Resend email' from the Actions menu. This will send the participant an email reminder to take part in your experiment. You may also wish to use this action to encourage participants to continue with their experiment if they have not yet returned to complete it.

We recommend advising participants to check their spam and junk folders, as sometimes these recruitment emails can be misdirected there!

Add new participants

You can add new participants to your experiment at any time: simply upload a new .csv, .xlsx, or .ods file with email addresses and IDs you wish to add - these will be added to your list of emails and IDs, without overwriting the existing ones. Once you have uploaded your emails and IDs, the Status will show as Pending in your Participant tab. You must click Activate in the 'Activated' column (or Activate All on the top right) before your participants will be able to start your experiment. Once you have done this, the 'Status' and 'Activated' columns will show the participant as Activated until they start your experiment, as shown below:

The Participant tab shows your participants as Pending or Activated

Email ID


Identifying Recruitment Policy
This is an identifying recruitment policy, as it requires participant email addresses

This recruitment policy allows you to define a list of email addresses for participants, and requires you to set up a unique public ID for each participant in advance. Unlike Email Shot (which generates a unique link) the email will contain a generic link to a login page where the participant must use their unique public ID. With the link and public ID, the participant would be able to log in again to resume an experiment at a later time. However, nothing prevents the participant from sharing their link and public ID with another person.


Customise email

You can customise the email you send to participants by selecting a Customise Recruitment Email from your Recruitment tab settings as shown below:

A screenshot of the Recruitment Tab of the Experiment Builder. The Email ID recruitment policy has been chosen, and the Settings button has been clicked to show the Customise Recruitment Email option.

Fill in the Subject and Body boxes with customised information you wish to display to your participants. Make sure you include the tag {{url}} in your email where you would like to place the recruitment link. You can also add in the participant's name (as it appears in your Participants tab) using the tag {{name}}. The email can be further customised via HTML formatting.

Resend email

From your Participants screen you can select 'Resend email' from the Actions menu. This will send the participant an email reminder to take part in your experiment. You may also wish to use this action to encourage participants to continue with their experiment if they have not yet returned to complete it.

We recommend advising participants to check their spam and junk folders, as sometimes these recruitment emails can be misdirected there!

Add new participants

You can add new participants to your experiment at any time: simply upload a new .csv, .xlsx, or .ods file with email addresses and IDs you wish to add - these will be added to your list of emails and IDs, without overwriting the existing ones. Once you have uploaded your emails and IDs, the Status will show as Pending in your Participant tab. You must click Activate in the 'Activated' column (or Activate All on the top right) before your participants will be able to start your experiment. Once you have done this, the 'Status' and 'Activated' columns will show the participant as Activated until they start your experiment, as shown below:

The Participant tab shows your participants as Pending or Activated

3rd Party: Overview


Gorilla offers built-in integration with a number of popular participant recruitment services. Click the recruitment service you want to use for details on how to set this up in Gorilla:

Recruitment services frequently used by behavioural scientists and integrated with Gorilla

Alternatively, you can use the generic Third Party recruitment policy to set up a custom integration with any third-party recruitment service of your choice, such as the following:

Services that can be used with Gorilla's Third Party Recruitment Policy to obtain population representative samples or target specific demographics

'Free' recruitment options (you take part in others' experiments and they do yours in return):

Prolific


Anonymous Recruitment Policy
This is an anonymous recruitment policy, unless you explicitly collect identifying data

This recruitment policy allows you to recruit participants via the 3rd party tool Prolific.

You might want to consider encouraging your participants to click the 'Open Study in New Window' button on Prolific so that they get your study fullscreen.

We also recommend you read Prolific's Gorilla Integration Guide in addition to their general use documentation.

To set up your experiment correctly and connect your Gorilla Experiment to Prolific:
  1. In Gorilla: On your experiment's 'Recruitment' page make sure you have selected 'Prolific' as your recruitment policy.

  2. In Gorilla: Copy the Gorilla Experiment URL provided.

  3. In Prolific: Paste the Gorilla Experiment URL provided into the 'Study URL' field in Prolific. Gorilla automatically captures the Prolific ID and Session ID and stores them in Gorilla as a participant's 'Participant Public ID' and 'Participant External Session ID' respectively. These will then be visible in your Gorilla metrics - you will need to 'Unblind' your data to view the public ID within your metrics.

  4. In Gorilla: On your experiment's Finish node(s), under Onward URL, enter your Prolific Redirect URL.


Are you recruiting for a longitudinal/multi-part study on Prolific? You'll need to think about the Prolific/Gorilla integration in a slightly different way. In Gorilla, you run your study in one experiment tree using Redirect Nodes instead of Delay Nodes. However, each part of your study needs to be listed as a separate study on Prolific, whilst using the same Gorilla recruitment link for each one. Take advantage of Prolific's Custom Allowlist (scroll down to 'Option 2: Use a custom allowlist) to only invite the participants who completed the first part back to the remaining sessions of your experiment. Take a look at our longitudinal/multi-part studies support page and Prolific's integration guide "How do I set up a longitudinal (multi-part) study on Gorilla and Prolific" (scroll to the bottom of the linked page) for more information.

Mismatch in spaces available on Prolific and Gorilla: If more spaces are available for an experiment on Prolific than in Gorilla, participants will see an 'Experiment Full' warning when trying to access the study. We have two ways of preventing this: 1) Participants who either manually return the study on Prolific, or are rejected by Prolific due to a timeout, will automatically be rejected on the Gorilla side as well. These participants will show up in your Participants tab as RejectedManual. Find out more about participant status and progress in our Participants Guide. 2) If participants from Prolific try to access an experiment that is full, the owner and collaborators on the Gorilla project will be automatically notified by email. The project owner can then increase the spaces available on Gorilla or decrease the spaces available on Prolific. If you are experiencing issues with a disconnect between your recruitment target in Gorilla and in Prolific, please contact support.


Sona Systems®


Anonymous Recruitment Policy
This is an anonymous recruitment policy, unless you explicitly collect identifying data

This recruitment policy allows you to recruit participants via the 3rd party tool Sona Systems®.

Use Case: Use this when you want to recruit your participants using Sona Systems®.

When set up correctly, by integrating your experiment with Sona Systems®, Sona will be able to automatically grant credit to your participants upon their completion of your Gorilla Experiment. This eliminates the need for researchers to manually grant credits.

To set up your experiment correctly and connect your Gorilla Experiment to Sona:
  1. In Gorilla: On your experiment's 'Recruitment' page, make sure you have selected 'Sona Systems' as your recruitment policy.
  2. In Gorilla: Copy the Gorilla Experiment URL provided.
  3. In Sona: Paste the Gorilla Experiment URL provided into the 'Study URL' field in Sona. Gorilla automatically captures Sona's SURVEY_CODE (an ID provided by Sona that is unique to the participant) and stores it as the participant's Public ID.
  4. In Gorilla: On your experiment's Finish node(s), under Onward URL, enter your Gorilla Onward URL from Sona. The participant will be automatically granted the credit once they are redirected back to the Sona Systems site. If you are using a Redirect node instead of the Finish node, you will need to add in a setting to the 'Append Public ID' box on the Redirect node. Sona recognises the parameter 'survey_code' (an ID provided by Sona that is unique to the participant), and so you need to type survey_code into the Public ID setting.

If you need further information about connecting your experiment with Sona you can view the Sona Systems Support page.


Amazon Mechanical Turk


Anonymous Recruitment Policy
This is an anonymous recruitment policy, unless you explicitly collect identifying data

This recruitment policy allows you to recruit participants via the 3rd party tool Amazon Mechanical Turk (MTurk).

Use Case: Use this when you want to recruit your participants from MTurk.

Your participants will start in Gorilla, once they complete your experiment (by entering a Finish Node) they will then be shown their MTurk completion code.

To connect your Gorilla experiment to MTurk, simply use the Gorilla URL as the URL for your HIT.

Gorilla will automatically show your participants a unique completion code, which they can use to confirm that they have completed the HIT. These completion codes will be included in your data download, so you can check them to ensure that they match those submitted for your HITs

Set Up - how to connect your Gorilla experiment to Amazon Mechanical Turk:
  1. In Gorilla; copy your experiment's URL
  2. In MTurk; use your Gorilla experiment's URL for your MTurk 'HIT'. Need more detailed information on how to set up Amazon Mechanical Turk with Gorilla? Check our our MTurk Walkthrough!
Pro Tip

Sometimes you will not wish to show a participant a completion code, such as when you want to reject a participant.

A Reject Node can be used to end the experiment for that participant, and can show them a completion code.

CloudResearch: Connect


Anonymous Recruitment Policy
This is an anonymous recruitment policy, unless you explicitly collect identifying data

This recruitment policy allows you to recruit participants via the 3rd party tool CloudResearch, specifically their crowdsourcing platform Connect.

Use Case: Use this when you want to recruit your participants from CloudResearch's Connect crowdsourcing platform.

To set up your experiment correctly and connect your Gorilla Experiment to CloudResearch: Connect
  1. In Gorilla: On your experiment's 'Recruitment' page, make sure you have selected 'CloudResearch: Connect' as your recruitment policy.

  2. In Gorilla: Copy the Gorilla Experiment URL provided.

  3. In CloudResearch: Paste the Gorilla Experiment URL provided into the 'Project Link' section in Connect. Gorilla automatically captures the CloudResearch: Connect participantId and stores it in Gorilla as the Participant Public ID. This will appear on the Participants tab of your Gorilla experiment. It will also be included in your downloadable Gorilla data if you tick the 'Unblind' setting when generating your experiment data. Gorilla also automatically captures the CloudResearch: Connect projectID and stores it in Gorilla as the External Session ID. This will be included in your downloadable Gorilla data.

  4. In Gorilla: On your experiment's Finish node(s), under Onward URL, enter your CloudResearch redirect URL. If you prefer to use a completion code, copy the completion code from CloudResearch and display it on the final page of your experiment. Instruct your participants to return to CloudResearch and enter the completion code to confirm they have completed the study.

Pro Tip

As well as Connect, CloudResearch offers two other participant pools: MTurk Toolkit and Prime Panels. For MTurk Toolkit, use the CloudResearch: MTurk Toolkit recruitment policy. For Prime Panels, use the 3rd Party recruitment policy and set the Inbound Participant ID Parameter to aid.

CloudResearch: MTurk Toolkit


Anonymous Recruitment Policy
This is an anonymous recruitment policy, unless you explicitly collect identifying data

This recruitment policy allows you to recruit participants via the 3rd party tool CloudResearch, specifically MTurk Toolkit, which sources approved participant groups from Amazon Mechanical Turk.

Use Case: Use this when you want to recruit your participants from CloudResearch's MTurk Toolkit platform.

To set up your experiment correctly and connect your Gorilla Experiment to CloudResearch: MTurk Toolkit
  1. In Gorilla: On your experiment's 'Recruitment' page, make sure you have selected 'CloudResearch: MTurk Toolkit' as your recruitment policy.
  2. In Gorilla: Copy the Gorilla Experiment URL provided.
  3. In CloudResearch: Paste the Gorilla Experiment URL provided into the 'Survey Hyperlink' section in MTurk Toolkit. If you choose to auto-capture worker information from the URL, Gorilla will automatically capture the CloudResearch: MTurk Toolkit workerId and store it in Gorilla as the Participant Public ID. This will appear on the Participants tab of your Gorilla experiment. It will also be included in your downloadable Gorilla data if you tick the 'Unblind' setting when generating your experiment data. Gorilla also automatically captures the CloudResearch: MTurk Toolkit hitId and stores it in Gorilla as the External Session ID. This will be included in your downloadable Gorilla data.
  4. In CloudResearch: Decide whether you want to use a Fixed or Custom completion code. A Fixed code is the same for every participant, whereas a Custom code is different for each participant.
  5. In Gorilla: If using a Fixed completion code, copy the completion code from CloudResearch and display it on the final page of your experiment. If using a Custom completion code, open the Finish Node of your experiment and tick 'Show Completion Code' - this will generate a unique completion code for each participant. Finally, instruct your participants to return to CloudResearch and enter the completion code to confirm they have completed the study.
Pro Tip

As well as MTurk Toolkit, CloudResearch offers two other participant pools: Connect and Prime Panels. For Connect, use the CloudResearch: Connect recruitment policy. For Prime Panels, use the 3rd Party recruitment policy and set the Inbound Participant ID Parameter to aid.

Qualtrics


Anonymous Recruitment Policy
This is an anonymous recruitment policy, unless you explicitly collect identifying data

This recruitment policy allows you to recruit participants via the 3rd party tool Qualtrics.

Use Case: Use this when you want to recruit your participants from Qualtrics or else link your qualtrics surveys with your Gorilla experiments.

Your participants will start in Qualtrics, and then be passed to Gorilla to complete the experiment. When set up correctly, a participant's 'Response ID' in Qualtrics will be identical to their PublicID in Gorilla. Allowing you to easily match up data from both systems.

Set Up - how to connect your Gorilla experiment to your Qualtrics survey:
  1. In Qualtrics; in your Survey Flow, add an 'End of Survey element'
  2. Click 'Customise', and under 'Override Survey Options', choose 'Redirect to a URL...'
  3. Enter your Gorilla experiment's URL here as the redirect URL.
  4. In Gorilla; make sure you have selected 'Qualtrics' as your experiment's recruitment policy. This allows Gorilla to automatically capture the parameters provided by Qualtrics.

Qualtrics Panel


Anonymous Recruitment Policy
This is an anonymous recruitment policy, unless you explicitly collect identifying data

This recruitment policy allows you to recruit participants via the 3rd party tool Qualtrics Panel.

Use Case: Use this recruitment policy when you want to recruit your participants from a Qualtrics Panel.

Your participants will need to start in Qualtrics, and then be passed to Gorilla to complete the experiment, before being passed back to the Qualtrics Panel again to flag that they have completed the experiment.

When set up correctly, a participant's 'Response ID' in Qualtrics will be identical to their PublicID in Gorilla. Allowing you to easily match up data from both systems.

Set Up - how to connect your Gorilla experiment to your Qualtrics survey:
  1. In Qualtrics; in your Survey Flow, add an 'End of Survey element'
  2. Click 'Customise', and under 'Override Survey Options', choose 'Redirect to a URL...'
  3. Enter your Gorilla experiment's URL here as the redirect URL.
  4. In Gorilla; make sure you have selected 'Qualtrics Panel' as your experiment's recruitment policy. This allows Gorilla to automatically capture the parameters provided by Qualtrics.
  5. In Gorilla; On your Finish node(s), under Onward URL, enter your 'Qualtrics return URL'.
  6. Gorilla will automatically append the participants's PublicID and other necessary variables to the URL for you, so you can leave Append PublicID blank.
Warning

Make sure all your Finish nodes redirect back to Qualtrics, otherwise Qualtrics has no way of knowing that they've finished!

Kantar Profiles


Anonymous Recruitment Policy
This is an anonymous recruitment policy, unless you explicitly collect identifying data

This recruitment policy allows you to recruit participants via the 3rd party tool Kantar Profiles.

Use Case: Use this recruitment policy when you want to recruit your participants from Kantar Profiles.

To connect your Gorilla experiment to Kantar Profiles, simply use the Gorilla URL as the URL for your study.

Gorilla will automatically capture your participants' parameters and append them to any return URLs, allowing you to track if they have completed the study.

Set Up - how to connect your Gorilla experiment to CloudResearch:
  1. In Gorilla; copy your experiment's URL
  2. In Kantar Profiles; use your Gorilla experiment's URL for your Kantar Profiles study.

Third Party


Anonymous Recruitment Policy
This is an anonymous recruitment policy, unless you explicitly collect identifying data or your recruitment provider uses identifying participant IDs

This recruitment policy allows you to recruit participants via a 3rd party company or organisation, or to send participants to Gorilla from another platform such as REDCap.

For some popular recruitment services, such as Prolific, Sona Systems and Amazon Mechanical Turk, there are specialised recruitment polices available (see the menu on the left). If you are using a third party recruitment provider for whom we do not have a built-in integration, then you will need to set up the integration yourself by following the steps below.


On the Recruitment tab of your experiment, click 'Change Recruitment Policy' and select the Third Party recruitment policy. Your Recruitment Policy section should now look like this:

Screenshot of 3rd Party recruitment policy showing unique URL including ?external_id=[PARTICIPANT_ID] and 'Configure Inbound URL' button

The Unique URL is the link to the experiment. The part at the end, ?external_id=[PARTICIPANT_ID], is called a query string. This is how the participant ID will be passed from your recruitment service to Gorilla. The part before the equals sign, external_id, is the name of the participant ID parameter. The part after the equals sign, [PARTICIPANT_ID], is a placeholder for each participant's individual ID. If your recruitment service requires you to manually create each participant's unique URL, you can do this by replacing [PARTICIPANT_ID] with the participant's specific ID. More commonly, the recruitment service will append the participant's ID automatically. In this case, you should post only the bare experiment URL - i.e., everything up to and excluding the ? - on your external recruitment service.

By default, Gorilla assumes that the participant ID will be called external_id. If your external recruitment service has the ability to set the name for the participant ID parameter in the query string, you should set this to external_id to match what Gorilla expects. More commonly, the external recruitment service will have its own name for the participant ID, and you may not be able to change this. For example, CloudResearch's Prime Panels service uses the name aid for the participant ID. If this is the case for your recruitment service, you will need to click 'Configure Inbound URL' to update the name of the participant ID parameter on the Gorilla side:

Screenshot of 3rd Party recruitment policy.'Configure Inbound URL' button is highlighted

This will open the following window:

Screenshot of Configure Inbound URL window, containing a text field labelled 'Inbound Participant ID Parameter'

In the 'Inbound Participant ID Parameter' box, enter the name your recruitment service uses for the participant ID in the query string. For example, if using CloudResearch's Prime Panels, you would enter aid. Then click Save. You will see that the Unique URL on the Recruitment tab has now updated to replace external_id with your new parameter name:

Screenshot of 3rd Party recruitment policy showing unique URL. external_id has been replaced with aid

This means that when participants come in from your external service, Gorilla will know that the aid parameter in the URL corresponds to the participant ID. Gorilla will then save this as the Participant Public ID to enable you to link your data across platforms. The Participant Public ID will be viewable on the Participants tab and automatically included in your data. You can also send the participant ID back to the original platform, or on to another platform, by using the 'Append Public ID' setting on the Finish Node or the Redirect Node of your experiment.

Optionally, you can also pass additional information from your external recruitment service to Gorilla. You can do this by adding further parameters to the query string on the recruitment service side. For example, let's say your experiment has the base URL shown in the screenshots above: https://research.sc/participant/login/dynamic/109FB54F-804C-4203-A24E-56FFFCC0D303. You have a participant whose external_id is 12345, and whose completion_code is 67890. To pass both of these pieces of information to Gorilla, you would construct the following URL on the recruitment service end:

https://research.sc/participant/login/dynamic/109FB54F-804C-4203-A24E-56FFFCC0D303?external_id=12345&completion_code=67890

As shown in this example, the first parameter in a query string must be preceded by a ?. Any subsequent parameters must be preceded by a &.

Any additional data passed to Gorilla via URL parameters will be stored as embedded data/Store data. This can either be retrieved within a task using the Store (the name of the Store field will be the parameter name from the URL), or passed back to your recruitment service or on to another platform using the 'Append Store/Embedded Data' setting on the Finish Node or the Redirect Node.

Warning

If the participant ID is not passed through correctly, participant data may be mis-identified, or you may not be able to link your data across platforms. We highly recommend piloting your third party recruitment setup with at least a few real participants before launching your study. And if you need assistance with getting everything set up, don't hesitate to contact the support desk!


Reward Node

You want to reward your participants for taking part in your experiment, but you don't use a recruitment service that pays participants? Consider using a Reward Node, where you can send a voucher or a gift card to your participants and make sure to compensate them for the time and effort they put in when taking part in your research study.

There are a few reward platforms you could use to implement a reward. Have a look at their websites:

  1. BHN Rewards
  2. Tango
  3. XOXOday