Sigma Validation, Marketing Consultants, Surveys

The following research companies demonstrate their commitment to excellence through using Sigma Validation's Duplicate Number® Search.

These vendors take an "extra step" to help ensure the respondent-level quality of their clients' market research studies.

The companies listed below go above and beyond ordinary research standards to provide their clients with the highest quality research possible.

The following companies use Sigma Validation's Duplicate Number® Search on all qualifying projects*.














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The following companies use Sigma Validation's Duplicate Number® Search on most qualifying projects*.










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The following companies use Sigma Validation's Duplicate Number® Search on selected qualifying projects*.













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The following companies use Sigma Validation's Duplicate Number® Search based on client request.
























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*Qualifying projects are consumer research studies that include a past-participation screener.