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A Guide From Domandata

How to Choose a Participant Recruitment Platform

Written by Domandata, which makes a survey platform. We name our product where it fits and say where another tool fits better. Claims about other tools link to their own documentation, checked ; confirm anything decisive with the vendor or your institution.

Most online studies in the social and behavioral sciences recruit participants through a platform rather than a mailing list. The options fall into three groups: self-serve participant pools, aggregated market-research panels, and probability panels commissioned from survey firms.

This guide explains the trade-offs that matter for research, from who is in the sample to fraud prevention and fair pay, and which platforms fit which kind of study.

The short answer

For fast, affordable online samples, Prolific (U.S., U.K., Europe, and other mostly OECD countries) and CloudResearch Connect (U.S. only) are the usual academic choices. For larger or harder-to-reach samples, use an aggregated panel such as CloudResearch Prime Panels or Cint. When the research question needs population estimates, commission a probability sample such as Ipsos KnowledgePanel. Whichever you choose, your survey tool must pass participant IDs in and send people back with the right outcome.

What to weigh when choosing a recruitment platform

  1. 1

    What kind of sample you need

    Opt-in pools are fast and affordable but are not probability samples. They work well for experiments that estimate treatment effects, and less well for estimating how common an opinion is in a population. For population estimates, budget for a probability panel.

  2. 2

    Where participants live

    Pools differ in country coverage. Check that the platform reaches your target population in enough numbers after your screening criteria, not just in total.

  3. 3

    Fraud and data quality

    Bots, duplicate accounts, and AI-written answers are now routine threats. Look for identity verification, ongoing monitoring, and the ability to report or reject low-quality submissions, and keep your own attention and quality checks in the survey.

  4. 4

    Fees and fair pay

    Most self-serve platforms charge participant pay plus a percentage fee, often lower for academic accounts. Some enforce a minimum hourly rate. Your ethics board may set its own pay expectations.

  5. 5

    Targeting and longitudinal follow-up

    Prescreening filters, quotas, and the ability to invite the same participants back for later waves vary by platform and can decide feasibility for panel studies.

  6. 6

    Survey-tool handoff

    Your survey must capture each participant's platform ID and redirect them back as complete, screened out, or over quota. Test the full loop with a small pilot before launching.

Platforms by kind of study

Fast online samples outside the U.S. or across several countries

A large self-serve pool concentrated in OECD countries, with free prescreening and a minimum hourly reward.

Prolific

Self-serve online participant pool for academic and commercial research, with participants mostly in OECD countries.

Pricing model
Pay as you go: participant rewards plus a percentage platform fee, lower for academic and non-profit accounts with an institutional email. No monthly fee.
Where it runs
Recruitment only; links to a study built in any survey or experiment tool.

Strengths

  • Identity verification at sign-up and optional in-study checks for bots and AI-written answers.
  • Hundreds of free prescreening filters and representative samples at no extra cost.
  • Enforces a minimum hourly reward, which simplifies fair-pay requirements in ethics review.

Watch out for

  • An opt-in, non-probability pool, so population estimates need care.
  • Some data-quality guarantees apply only to particular integrations.

Sources:Prolific PricingWho Is on ProlificProlific Data Integrity

U.S. samples and multi-wave studies

Built with academic users in mind, with vetted U.S. participants and longitudinal waves.

CloudResearch Connect

Self-serve participant platform aimed at academic researchers, with US participants and support for multi-wave studies.

Pricing model
Participant pay plus a percentage service fee, lower for academic and non-profit accounts, with an introductory no-fee period for new academic accounts.
Where it runs
Recruitment only; participants are currently in the U.S.

Strengths

  • Participants are vetted at sign-up and monitored on every study for fraud and AI-generated content.
  • Demographic, quota, and scale-score targeting.
  • Longitudinal waves for following the same participants.

Watch out for

  • U.S. participants only.
  • An opt-in, non-probability pool.

Sources:Connect FAQConnect for Researchers

Large, rare, or geographically targeted samples

Aggregated panels reach far more people than a single pool, at the cost of more varied participant quality. Plan stronger in-survey quality checks.

CloudResearch Prime Panels

Aggregation of opt-in market-research panels for large samples and hard-to-reach groups, including international and geographically targeted samples.

Pricing model
Quote-based; participant compensation is set by the supplying panels.
Where it runs
Recruitment only; links to a study built in your survey tool.

Strengths

  • Reach far beyond a single participant pool.
  • Screening of participants for bots and fraud before they enter a study.

Watch out for

  • Panels vary in how participants are recruited and paid.
  • You do not control participant compensation.

Sources:Prime Panels

Cint (Theorem)

Global research-sample marketplace; its Theorem product offers prepaid U.S. samples for academics.

Pricing model
Theorem is prepaid at a fixed price per complete, paying only for accepted responses; the wider Cint marketplace is sold through its sales team.
Where it runs
Recruitment only; Theorem documents a Qualtrics connection.

Strengths

  • Very large reach through many supply partners across many countries.
  • Theorem samples are matched to the U.S. Census on core demographics.

Watch out for

  • Aggregated opt-in supply, so quality checks in your own survey still matter.
  • Theorem is U.S.-only and built around Qualtrics.

Sources:Theorem by CintHow Cint Works

Population estimates

KnowledgePanel is a probability sample recruited by address. YouGov uses matched and weighted non-probability samples and has an academic team for commissioned studies. Know which one your inference needs.

Ipsos KnowledgePanel

Probability-based U.S. online panel recruited by address-based sampling, often used for government and academic research.

Pricing model
Commissioned as a custom study; quote-based.
Where it runs
Fielded by Ipsos; households without internet receive a device and access.

Strengths

  • A true probability sample, including households that are offline.
  • Supports population inference that opt-in pools cannot.

Watch out for

  • Commissioned rather than self-serve, and considerably more expensive than opt-in samples.

Sources:KnowledgePanelKnowledgePanel Methodology

YouGov

Online panel that draws matched samples and weights them to national populations, with an academic team for commissioned studies.

Pricing model
Commissioned through the academic research team; quote-based.
Where it runs
Fielded by YouGov, including cross-national, multi-wave, and embedded-experiment designs.

Strengths

  • Experienced with academic designs, recontact studies, and survey experiments.
  • National samples in many countries from one vendor.

Watch out for

  • Uses non-probability sampling with matching and weighting, by its own description.

Sources:YouGov MethodologyYouGov Academic Research

The survey tool on your end

Any of these platforms works with a survey that captures IDs and redirects correctly. Domandata has guided setups for Prolific, CloudResearch Connect and Prime Panels, Cint, and Rep Data, and can launch Prolific and Connect studies directly. Qualtrics works with all of them through URL parameters and redirects.

DomandataOur product

Browser-based survey platform built for academic social-science research: survey experiments, conjoint, and analysis-ready data.

Pricing model
Free plan for drafting and previewing; fielding a study, Flow logic, and exports need a paid individual or team plan with published self-serve pricing.
Where it runs
Cloud only, on U.S.-based infrastructure providers.

Strengths

  • Randomized treatment arms (weighted, stratified, or balanced) with the assigned condition saved in every export.
  • Conjoint, MaxDiff, list experiments, and reaction-time tasks built in, without custom JavaScript.
  • Native SPSS (.sav) and Stata (.dta) exports with a generated codebook, plus Qualtrics .qsf import.
  • Links OSF preregistrations and deposits replication materials to Harvard Dataverse or Zenodo.

Watch out for

  • Does not sign HIPAA Business Associate Agreements, so it is not suitable for studies that require one.
  • Cannot be self-hosted, and the data-hosting region is not fixed by contract.
  • The free plan cannot collect responses; fielding a study requires a paid plan.
  • A newer, smaller vendor: its SOC 2 Type I audit is still in progress, which some IT reviews ask for.

Sources:Domandata PricingDomandata Trust Center

Qualtrics

Enterprise survey platform that many universities license campus-wide, and the default tool in much of academic survey research.

Pricing model
Usually an institutional license at no personal cost to students and staff, on terms set by your university's agreement. A capped free account is meant for trying the platform.
Where it runs
Cloud only. Publishes ISO 27001 and FedRAMP certifications.

Strengths

  • If your university licenses it, it is already paid for and usually reviewed by IT.
  • Mature, deep feature set, including Survey Flow randomizers and quotas.
  • Exports to CSV, Excel, and SPSS.

Watch out for

  • Access depends on your institution; leaving it can mean losing the license.
  • The free account caps responses, active surveys, and questions per survey, which rules out most studies.

Sources:Qualtrics Free AccountsQualtrics Account CreationQualtrics RandomizerQualtrics Security

Before you launch on a recruitment platform

  • Participant IDs are captured in your data
  • Complete, screen-out, and over-quota redirects each return the right code
  • Pay meets the platform's minimum and your ethics board's expectations
  • Prescreening matches the eligibility criteria in your protocol
  • Attention and quality checks are in the survey, not left to the platform
  • A small pilot ran through the platform itself, not just a preview link
  • You know how to reject or replace low-quality submissions

Frequently Asked Questions

Should I use Prolific or CloudResearch Connect?

Connect currently recruits only U.S. participants, so for samples elsewhere Prolific is the natural choice. For U.S. studies both are widely used; compare fees, the prescreening criteria you need, and how each handles longitudinal follow-up before deciding.

Are online participant pools representative?

No. Prolific, Connect, and aggregated panels are opt-in, non-probability samples, even when quotas match census demographics. They suit experiments that estimate treatment effects; for population estimates, use a probability panel such as Ipsos KnowledgePanel and report the method.

How much should I pay participants?

Prolific enforces a minimum hourly reward and recommends a higher rate, and CloudResearch recommends a minimum hourly pay for Connect. Estimate completion time from a pilot, pay at least the platform minimum, and check whether your institution or ethics board sets a higher standard.

Keep Reading

Panel Recruitment Guide

IDs, screeners, quotas, and redirects, step by step.

Survey Experiments Guide

Plan conditions, power, and analysis before recruiting.

Why Domandata

Our own case for Domandata, and when to use another tool.

Domandata Integrations

Supported recruitment platforms and how each connects.