(Reuters) – The U.S. Centers for Disease Control and Prevention, facing a Freedom of Information Act lawsuit seeking a vast trove of data about the safety and side-effects of the COVID-19 vaccines, made a pledge in August.

The agency in court papers said that on or before Sept. 30, it would post on its website a “public use” set of data from about 10 million people who signed up for its “v-safe” program — a smartphone-based system that periodically sends people text messages and web surveys to monitor potential side effects from the Pfizer, Moderna and Johnson & Johnson COVID-19 vaccines.

But the CDC missed its deadline. A spokesperson cited a delay in “the technical and administrative processes” necessary to post on the agency’s website, but said it hopes to have the information up by late November or early December.

In the meantime, the CDC handed over the v-safe data (minus personal identifying information) to the plaintiff in the FOIA case, the Informed Consent Action Network, or ICAN, a Texas-based nonprofit that says it opposes “medical coercion” in favor of individual healthcare choices.

ICAN crunched the numbers on its own and came up with some statistics that its lawyer says appear to be “alarming.”

According to ICAN, 7.7% of the v-safe users — 782,913 people — reported seeking medical attention via a telehealth appointment, urgent care clinic, emergency room intervention or hospitalization following a COVID-19 vaccine.

About 25% of v-safe users said they experienced symptoms that required them to miss school or work or prevented them from doing other normal activities, according to ICAN’s “dashboard” that summarizes the results.

There’s no way, however, based on the information collected, to determine whether the COVID-19 vaccines actually caused the ailments. ICAN’s analysis included responses reported beyond the first seven days post-vaccine and it counted all reports of people seeking medical attention up to a year after receiving the shot. ICAN did not specify when after vaccination they received the care, nor did the data indicate what the care was for.

I asked a CDC spokesperson what the agency made of ICAN’s calculations. Are the numbers accurate?

The CDC “cannot comment on analyses conducted outside of the agency that we have not seen,” the spokesperson said via email, but added that v-safe data “have shown low rates of medical care after vaccination, particularly hospitalization.”

In the first week after getting the shot, the spokesperson continued, “reports of seeking any medical care (including telehealth appointments) range from 1-3% (depending on vaccine, age group and dose).”

She pointed me to a report looking at the first six months of v-safe data to back up the assertion. In addition, another CDC spokesperson said that agency personnel made follow-up calls to any v-safe users who reported seeking medical attention.

But ICAN counsel Aaron Siri of Siri & Glimstad, who led the FOIA litigation against the agency, said that because some vaccine-related adverse effects (chronic arthritis, thrombocytopenia, Guillain-Barré syndrome, myocarditis and more) can appear weeks after vaccination, it’s important to broaden the time frame beyond the one-week window in research the CDC cited.

“This is a large and concerning number of negative health impacts,” Siri said of ICAN’s conclusions, adding that he’s aware of no comparable public data for other vaccines.

A Pfizer media representative in an email said that the company’s vaccine has “a favorable safety profile and high level of protection against severe COVID-19 disease and hospitalization.”

Representatives from Moderna and Johnson & Johnson did not respond to requests for comment.

Until ICAN’s suit, the v-safe data was not public, though specific findings have been reported by the CDC and medical journals.

The data has its limits. The CDC asked v-safe users to self-report a range of post-vaccine symptoms such as headache, joint pain and fatigue, and (irrespective of whether they sought medical attention) to categorize the ailments as mild, moderate or severe. The agency queried v-safe users about their health every day for the first week following vaccine, and then at various points afterwards for the next 12 months, gathering a total of 146 million records.

In addition to the dashboard summary, ICAN on its website has made the underlying dataset available for public download. Reuters did not independently verify ICAN’s analysis of the information.

Siri, a 2004 University of California Berkeley School of Law grad who got his start at Latham & Watkins, is no stranger to FOIA fights. Last year, he sued the Food and Drug Administration to make public the data it relied on to license Pfizer-BioNTech’s COVID-19 vaccine. The agency unsuccessfully argued that it needed up to 76 years to review and release all the information.

Siri filed suit against the CDC on behalf of ICAN last year in Austin, Texas, federal court to get the v-safe data.

For concerned members of the public wondering about vaccine safety, it’s hard to know what to think.

The CDC — which should be the gold standard for accurate information — still hasn’t made the v-safe information publicly available itself, although it seems to have fulfilled a FOIA obligation by giving it to ICAN.

It’s notable that ICAN has a history of vaccine skepticism. Its founder, Del Bigtree, is known for producing the 2016 documentary “Vaxxed: From Cover-Up to Catastrophe,” which may be why the group’s findings have received scant media coverage.

Look. I believe vaccines save lives, and I eagerly received COVID-19 shots. I have no interest in being an anti-vax mouthpiece.

But I also believe in maximum government transparency.

Siri said that the v-safe information offers a unique window: millions of people, all “answering identical questions, making the data susceptible to calculating a rate for each harm reported.” He has point.

It indicates that, at a minimum, hundreds of thousands of people experienced health events that they considered “severe” following the shot and sought medical care.

Moreover, for those still struggling to recover and believe the vaccine is to blame, legal recourse is limited.

The COVID-19 vaccine makers are indemnified by the government, and all injury claims are adjudicated by an obscure tribunal, the Countermeasures Injury Compensation Program. Payouts are limited to unreimbursed medical expenses and up to $50,000 a year in lost wages.

As of Sept. 1, the forum had received 7,084 claims alleging injuries or death from the COVID-19 vaccines. Three claims have been deemed eligible for compensation and 42 have been rejected.

A spokesperson told me the compensation program is “actively bringing on additional administrative staff and claims reviewers to process these claims as quickly as possible.”

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