The WPP-owned research company is asking adults being selected for online research panels whether they have any children and if they mind them taking part in future child research panels.
The children's personal details are then recorded, and when specific panels are required the parents are again asked for permission for the children to take part.
Ralph Risk, Lightspeed marketing manager, said: "Lightspeed is able to provide companies access to this audience in an environment that is both safe for and relevant for children."
This new procedure meets with guidelines set by Esomar, the world association of opinion and market research professionals, and the Children's Online Privacy Protection Act.
Andrew Cayton, senior vice-president of European business development at Lightspeed, said: "As children become more sophisticated and savvy, their influence on purchase decisions increases and their attitudes become of greater importance to marketers and researchers."
The new selection criteria is already being used by the company's client base using Lightspeed's network of 17m households across 34 countries in Europe, North America and Asia Pacific.
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