Contents:
1. What is a Domain Expert?
2. What Domain Experts are available?
3. How are Domain Experts verified?
4. How to set up a study using Domain Experts
• Using Domain Experts in the API
• Using Domain Experts on the study set up page
5. How much should I pay Domain Experts?
6. Can I Refer a Domain Expert?

Prolific’s Domain Experts are vetted professionals and academics with proven subject matter expertise. Whether you're building, fine-tuning, or evaluating AI systems, they help you get fast, accurate, domain-specific data in fields like STEM, healthcare, and languages.

You can use our Domain Experts to:

• Validate model outputs for factual accuracy and technical soundness
• Train on expert-level data across highly specialized fields
• Get in-depth feedback on tone, structure, clarity, and real-world applicability of your content

They’re your go-to participants for specialist, context-aware insight—when precision really matters.

What is a Domain Expert?

Domain Experts are professionals or academics with verified, specialized knowledge in specific fields. They undergo rigorous vetting, including skills assessments, credential checks, and internal reviews to confirm their expertise.

Whether you're building a large language model, validating health-related content, or testing complex code snippets, Domain Experts ensure your data quality matches the sophistication of your task.

What Domain Experts are available?

How are Domain Experts verified?

We use multiple layers of verification to ensure expert quality:

• Skills assessments: Participants complete tests tailored to their claimed expertise. Only top scorers are admitted to our expert pool.
• Academic and professional credentials: We review qualifications, publication history, h-index scores, and more.
• Work experience: We validate hands-on industry or research experience to ensure practical knowledge.

How to set up a study using Domain Experts

Using Domain Experts in the API

You can access Domain Experts directly via our API.

1. Discover available experts using Custom Groups.
2. Apply expert filters with guidance from our filter documentation.
3. Launch your study with a filter for your chosen expert group.

{
  "internal_name": "A sample study for domain experts",
  "name": "A sample study for domain experts",
  "description": "<p>This study uses domain experts in Javascript</p>",
  "external_study_url": "<https://www.example.com>",
  "reward": 7000,
  "total_available_places": 4,
  "prolific_id_option": "not_required",
  "estimated_completion_time": 60,
  "filters": [
    {
      "filter_id": "javascript",
      "selected_values": [
        "0"
      ]
    }
  ],
  "study_type": "SINGLE",
  "completion_codes": [
    {
      "code": "C1N88OPQ",
      "code_type": "COMPLETED",
      "actions": [
        {
          "action": "MANUALLY_REVIEW"
        }
      ]
    }
  ]
}

Using Domain Experts on the study set up page

To recruit Domain Experts in your study:

1. Navigate to 'Recruit participants' on your study set-up page
2. Select 'Find domain experts on Prolific'
3. Choose your required expertise from the dropdown menu

You'll see the number of available experts for your selected expertise before launching your study.

How much should I pay Domain Experts?

If you’re using Domain Experts in your studies, we recommend you pay them the following rates:

Can I Refer a Domain Expert?

At this time, there's no direct referral process for Domain Experts. However, you can invite people to Prolific using our Bring Your Own Participants (BYOP) feature. If they fill out their profiles thoroughly (especially the optional questions), we'll consider them for the Domain Expert pool during onboarding.