The measurement firms shared their plans Wednesday at a meeting hosted by the IAB, and attended by a number of industry organizations including the American Association of Advertising Agencies, the Association of National Advertisers, the Advertising Research Foundation, the Online Publishers Association, and the MRC.
Wednesday's meet-up resulted from an open letter sent by the IAB last month to comScore and Nielsen//NetRatings asking both firms to consider external audits.
Additional agreements and conclusions are expected to be revealed next week, according to Marla Nitke, IAB's director of marketing communications.
"A more formal announcement with details will be released jointly with the IAB in the near future," added a comScore spokesman.
Both comScore and Nielsen issued initial public responses soon after the IAB issued its open letter on April 20. Nielsen//NetRatings said it was in the process of securing third-party certification of its methodologies, and that it had already completed the Media Rating Council's pre-audit. comScore said it had recently opened its methodology to an evaluation by the Advertising Research Foundation, and that it planned to release the results publicly in the near future.