The Media Rating Council has reinstated accreditation for Nielsen’s national TV measurement after a 19-month suspension, giving the measurement giant a boost as it seeks to fend off growing competition in the coming upfronts.

The MRC suspended Nielsen’s national Television Audience Measurement service in September 2021 following a series of what the organization termed “non-compliance issues” stemming from panel degradation and problems servicing panelist homes during the pandemic. The move left essentially no service accredited by the country’s self-regulatory body for evaluating measurement quality, though rival Comscore has since applied for accreditation for its household-level TV measurement and iSpot.tv has applied for accreditation of the ad occurrence portion of its measurement.

Related: Comcast names Comscore as Nielsen alternative

Re-accreditation gives Nielsen something rivals lack, particularly for the coming upfront negotiations. But its relevance is mitigated by the fact that Nielsen has announced plans to stop using measurements of TV audiences based solely on its national panel and using C3 and C7 ratings by next year’s upfronts.

Nielsen has rolled out Nielsen One Ads and Nielsen One Content, based largely on big set-top boxes and smart TV data sets calibrated with data from the 41,000-plus household national panel. In its statement, the MRC for the first time indicated that Nielsen One-related aspects of the company’s measurement are now in at least the early stages of review.

Also read: Nielsen brings next-gen measurement to market

While the reinstatement covers most of Nielsen’s TAM service, it does not include Nielsen’s local TV measurement, which remains in accreditation suspension, or the Digital in TV Ratings (dTVR) component of the national service, the MRC statement said. The forthcoming integration of that device set return path and automated content recognition (ACR) data into Nielsen’s current service and Nielsen One “are in various stages of MRC audit and review,” the statement said, and are not accredited.

Those aspects of MRC evaluation appear to have begun earlier this year, as MRC CEO George Ivie late last year indicated that Nielsen had not begun the Nielsen One accreditation process at that time.

“Nielsen has undertaken strong efforts to correct the issues that led to its loss of accreditation 19 months ago and to restore key aspects of its panel performance,” Ivie said in the statement. “The MRC’s audit has shown these efforts have been successful, and as a result, our TV committee and board agreed that accreditation should be reinstated. That said, there is still more work to be done both in the near and long term to ensure Nielsen’s National TAM measurements continue to meet our standards and the requirements of the industry.”

Specifically, he said that work includes ensuring the future incorporation of return path and ACR data and Nielsen validating and improving estimates of broadband-only households. The MRC is also looking for Nielsen to enhance disclosures to users about variability associated with its TV viewing estimates, Ivie said.

“These latter two commitments were especially critical to our decision to re-apply accreditation at this time,” Ivie said.

Measurement outage surprises, sometimes uncovered by TV networks themselves rather than disclosed first by Nielsen, have led to ongoing complaints by industry executives.

An audit committee of the MRC in November declined to recommend reinstating Nielsen’s accreditation, giving the company a list of items to be addressed, which apparently have been.