The main group promoting state vouchers to help pay private school tuition bought full-page newspaper ads Friday seeking to counter a Deseret Morning News story that evaluated whether vouchers would truly make tuition affordable.

The newspaper had reported Thursday that even if voters approve giving $3,000 a year per child in vouchers to non-wealthy families, they would still need on average another $4,800 or so per child to pay typical private school tuition in Utah.

Parents for Choice in Education bought full-page ads, costing $8,400, Friday in the News and Salt Lake Tribune complaining that the News included in its calculations "a few 'Mercedes' schools that cost more than $50,000" a year in tuition, which it said distorts how affordable tuition can be, "making it too high."

"It was a very biased article," said Parents for Choice in Education spokeswoman Leah Barker. "There is a lot of debate about whether vouchers would make private schools do-able for low-income families. We want to make sure they understand the answer is yes."

But Lisa Johnson, spokeswoman for the anti-voucher Utahns for Public Schools, said, "The Deseret News analysis is consistent with all other impartial analyses. Numbers from PCE are inconsistent, and they're the only ones with motivation to mislead voters about the true cost of tuition and the true cost of the voucher law."

The News developed its data by calling all private schools listed by the State Office of Education. Some refused data or did not respond. The newspaper also excluded from calculations many treatment centers for drugs and other problems where overall treatment costs (usually very high) did not break out tuition for schooling there.

The research resulted in a database of 64 private schools, in which more than 13,700 of the 16,000-plus private school students estimated by the state are enrolled. It included five expensive boarding schools because they could qualify for vouchers.

The weighted average for tuition (taking into account how many students pay tuition at different levels) at all 64 schools was $7,824.

If boarding schools are removed from calculations, the weighted average for tuition is still $6,935 — or more than double what a voucher could provide. (But that still includes seven schools with tuition higher than $10,000, including well-known Rowland Hall-St. Marks at $13,692 and the Waterford School at $13,906.)

"That still includes some 'Mercedes' schools," Barker said, adding most families would not seek to attend there — so she argued that figures for them should not be included in stories about affordability even if such schools are eligible for vouchers.

She said, as the PCE ads said, "Most private schools have tuition under $5,000."

The News found and reported that also on Thursday. Of the 64 schools for which it had data, nine had tuition of less than $3,000 a year; seven had tuition between $3,001 and $4,000; 20 had tuition between $4,001 and $5,000; and 28 had tuition higher than $5,000.

In short, 56 percent of the public schools evaluated had tuition less than $5,000, and 44 percent were higher. But some schools have far more students than others. When considering how many students pay tuition at different levels, the weighted average for all was $7,824.

Still, Barker — who also is executive director of Children First Utah, which provides scholarships to private school students — says she knows from the checks she writes that more than 75 schools offer tuition of less than $5,000 a year, which she says would be affordable to most with a voucher.

Parents for Choice in Education had been reporting during this year's campaign that the average tuition bill in Utah is around $4,500 — far below what the News found. Barker said this week that PCE's calculations took into account only private schools with grades K-8, not K-12. The Morning News included all grades.

Barker said earlier this week, "We feel that there aren't a lot of private high schools in Utah ... and it's most important for children to get a solid foundation and that is going to happen in the beginning years. We use the K-8 formula because that is where this is going to matter the most."

Tuition for high schools is higher than at elementary schools, so excluding them lowers figures for typical tuition. High schools are also eligible for vouchers.

The voucher program facing a voter referendum on Nov. 6 would allow families to access private school tuition vouchers ranging from $500 to $3,000 per student, based on parents' income.