Since the advent of Arbitron’s PPM methodology, fundraising radiothons have been more carefully scrutinized at radio stations because of the perception that they are, in the words of one group PD, a “ratings killer.” But that fear may be overstated, according to new research from Edison Research principal Larry Rosin.

At the request of St. Jude Children’s Hospital, Rosin recently conducted several studies—pro bono—and presented the results at last weekend’s Country Cares For St. Jude Kids seminar in Memphis. (Read a wrap-up of the rest of that seminar.)

The image is out there that PPM is bad for ratings, said Rosin. He noted that the “metaphor of choice” PDs used to described their fear of radiothons’ impact on ratings was death, quoting programmers who used words like “killed” and “murdered” to describe what they felt could happen to their ratings. Rosin then proceeded to at least partially de-bunk that belief, noting that running a radiothon is not equivalent to “engaging in ratings ethnic cleansing.”

He cited numerous statistics from his research showing that while ratings did take a temporary hit during the two days of the radiothon, they bounced back quickly and by two weeks later were 1% higher on average for stations than they had been in the week before the radiothon.

“I don’t deny stations had to endure a little bit of ratings pain,” Rosin said, but they bounced back slightly higher than their pre radiothon levels, something Rosin partially attributes to the community goodwill generated by running a radiothon.

He also cautioned against applying PPM statistics about radiothons to diary markets. “One of the most distressing things I hear about is people questioning the radiothons in diary markets because of info they get in PPM markets,” Rosin said. “I highly doubt that is any kind of diary reality.”

In a summary Rosin described as a “quick editorial,” he urged stations to keep radiothons as part of their efforts to serve their communities. He noted that terrestrial broadcasters always say their advantage over Pandora is that they’re live and local, but these are the same broadcasters who are worried about doing radiothons.

In a separate survey of listeners to Country Cares stations who run radiothons, Rosin found that just 5% say they go out of their way to avoid listening to radiothons. And while most respondents said their listening habits don’t change during a radiothon, Rosin fund equal numbers of respondents who said radiothons made them listen more as those who said it makes them listen less.

Said Rosin, “running the Country Cares radiothon does make people feel more positive about your radio station, even if you lose ratings for those two days. You are enhancing your image all year long at your radio stations… You gain vastly more by running the radiothon than you lose in a little bit of ratings for those two days.”

He added, “I hope in the drive to monetize our stations’ profits, we don’t lose our souls in the process.”