When Annie Curtis ran away from home 15 years ago and police needed her picture, the photo came from a frame.

Not so for her 15-year-old sister, Sarah, who left her Clintonville home more than three months ago and hasn’t been seen since.

Finding a photo for Sarah’s missing-person poster was easy. Her Facebook and other social-media pages were filled with portraits Sarah had snapped of herself. Her family has photos of her with both serious and silly expressions, with different hair colors, with varying clothing.

Increasingly, the faces on the posters of missing teens aren’t taken by a school photographer or a parent but by the teens themselves. The selfies, as they’re known, are sometimes just days or hours old.

“In the old days, Mom would hand us a printed picture she took,” said Columbus police detective Jon Compson, who investigates missing-persons cases. “Nowadays, people are texting their pictures to us or accessing Facebook pages.”

In a flier sent out by Columbus police last week, a 12-year-old girl’s outstretched arm can be seen, likely holding the cellphone that took her picture.

Last month, a pouting 15-year-old girl snapped a photo of herself in a red tank top. Detectives said she was wearing a red tank top when she was last seen, similar to the one in the photo on the missing-person poster.

Both girls were found and returned home.

Lots of selfies can’t be put on the posters because they are inappropriate or in a group or shot from bad angles. Shots of girls looking too sexy or boys throwing gang signs won’t work, either.

“When you have a 16-year-old girl looking sultry in her picture, that’s not what we want to send out,” Compson said. “We look for the average picture.”

The Columbus missing-persons unit handles 3,000 cases a year, and posters are sent out for any “high-risk” person — anyone younger than 13 or older than 64, or when foul play is suspected.

Sarah Curtis’ disappearance is not considered high-risk. She left a note on April 24 saying she was staying at a friend’s house, though she wasn’t. She hasn’t returned home.

Sarah, the youngest of five children, was homeschooled and is whip-smart, said Annie, 31, her oldest sibling. “She’s a little more intellectual than most of her peers.”

Her family found her diary, where she wrote about a boy she had met. They think maybe she went somewhere with him, and they worry.

“She’s so vulnerable,” her sister said. “She’s 15.”

Two emails reassuring them of her safety were sent from a masked account, supposedly from Sarah, but the family isn’t sure.

“We don’t know still where she’s at,” Annie said. “She doesn’t give us any clues.”

Sarah’s family has been using social media to reach out to the public, and maybe to Sarah herself. More than 1,000 people have liked the “Help Find Sarah Curtis” page, where Annie Curtis and her family are posting photos, posters and messages directly to Sarah.

They’re using photos of her cat and other “things that will make her feel like she’s at home wherever she is,” Annie said.

She hopes that having lots of different photos will help people spot Sarah more easily.

“I want people to see how she’s transformed her looks,” Annie said. “She’s a chameleon. She’s a little actress.”

When Annie was 15, she ran away to Chicago with a friend for three weeks. Back then, there weren’t the same kind of cellphones or social media.

“Sarah’s generation ... she has 912 Facebook friends,” she said.

More than 153 million photos are tagged #selfie on Instagram. And fully 55 percent of millennials — those roughly ages 18 to 30 — say they have posted a selfie online, according to a study by the Pew Research Center.

All those photos aren’t just good for self-promotion; they help police, too.

“Especially if we have access to the social-networking site,” Compson said. “We want to show how tall they are or what does she look like when she has black hair, blond hair. The girls, especially, change their hair color quite often.”

Selfies are a documentation of daily life, said Pamela Rutledge, the director of the media psychology program at Massachusetts School of Professional Psychology. She’s not surprised to see selfies on missing-person posters.

“If you consider the difference between what someone looks like in a selfie and a school portrait, the selfie is much more reflective of what the child looks like,” Rutledge said.

And, she pointed out, there’s also the chance that the public will relate more to a candid shot taken by the child than to a sterile school photo.

Selfies “feel much more real,” she said. “This is a real person.”

©2014 The Columbus Dispatch (Columbus, Ohio)