By Jennifer Cockerell, Press Association Health Correspondent
Passport-style photographs are not a reliable way to validate a child’s identity at border control or in child protection cases, a study has suggested.
Psychologists at the University of Lincoln presented research participants with pairs of photos, some showing only infant faces and some showing both an infant and an older child’s face, and asked them to determine whether the image pair showed the same child or two different children.
For the images of children who were less than a year old, half of the pairs showed the same child while half showed different children.
Results demonstrated that, on average, participants made mistakes on more than a quarter (28%) of pairs.
Because UK child passports are valid for up to five years, the researchers also presented participants with photo pairs where an infant photo was shown with a photo of a child aged between four and five years old.
Half of the pairs showed pictures of the same child while half showed different children. Participants found this task more difficult, getting it wrong on more than a third (36%) of pairs.
Although gender could be determined from the child photos, accuracy was low when participants were asked to judge the gender of the under-ones.
Participants also found it difficult to ignore changes in hair colour or style across images, despite the likelihood of such changes for a child over a five-year period.
Researchers said previous studies using photographs of adults showed significantly higher accuracy rates, with participants matching photographs correctly around 90% of the time.
The results suggest that child passport photos are not as reliable as those of adults, and have implications for border control in countries which require children to travel on their own five-year passport for security purposes – including combating child trafficking – such as the UK, Canada, the United States and Australia.
Lead researcher Dr Robin Kramer, from the university’s School of Psychology, said: “The results of our experiments provide evidence that child facial photographs are ineffective for use in real-world identification situations such as border control or issues of child protection.
“Our findings suggest that alternative methods of identification should be considered.
“While these experiments have demonstrated that, on the whole, it is more difficult to match identities using infant faces rather than adult faces, the next step is to investigate why this is the case and how we might attempt to improve performance for real-world practitioners.”
The study is published in the journal PeerJ.