Childhood unpredictability may identify mental health risk missed by ACEs screening

Traditional adverse childhood experiences (ACEs) screening may not capture an important aspect of children's environments: whether daily life is predictable, according to a study published in Nature Mental Health.^1,2

Researchers assessed 29,861 children aged 0 to 17 years at 19 pediatric primary care clinics in Orange County, California, using the Pediatrics ACEs and Related Life-events Screen (PEARLS) and the 5-item Questionnaire on Unpredictability in Childhood (QUIC-5). Both measures were associated with mental health outcomes, but assessing unpredictability provided additional information about some children who had low conventional ACEs scores.

For pediatricians, Tallie Z. Baram, MD, PhD, a study author and child neurologist at the University of California, Irvine, said the findings address a limitation of existing ACEs screening: identifying which individual children may be particularly vulnerable.

Why might traditional ACEs screening miss some children?

ACEs screening assesses exposures such as abuse, neglect, and violence. Although these experiences are associated with physical and mental health outcomes at the population level, Baram said their ability to predict outcomes for an individual child is limited.

The researchers focused on unpredictability in children's social, emotional, and physical environments. The QUIC-5 measures this exposure using 5 questions and can be administered during well-child visits.

What did unpredictability screening identify?

Exposure to both ACEs and unpredictability increased with age, although both were present even among young children. Among those aged 0 to 4 years, 13% had at least 1 ACE and 23% had at least 1 form of unpredictability.

Higher scores on both PEARLS and QUIC-5 were associated with greater probabilities of depression, anxiety, externalizing problems, sleep disorders, headache, and abdominal pain. The 2 measures generally made independent contributions to identifying risk.

One finding involved children who had no conventional ACEs but substantial unpredictability. Among 50 children with a PEARLS score of 0 and QUIC-5 score of 4 or greater, the odds of a depression diagnosis were 11.7 times those among children who scored 0 on both measures.

Because the study was cross-sectional, however, the researchers could not determine the temporal relationship between unpredictability and diagnoses or establish that unpredictability caused the observed conditions.

Why could predictability matter to the developing brain?

Baram said the concept grew partly from observations that material resources alone did not appear to explain differences in children's outcomes. She described seeing children in environments with similarly limited resources but very different levels of daily structure.

In more structured environments, "You got up at 7:00 in the morning, you got breakfast with mom or dad, you went to school or kindergarten, somebody picked you up, you know who it's going to be. There was routine and structure," Baram said.

Research in animal models subsequently suggested that sequences of sensory input may influence developing neural circuits, according to Baram.

"Repeated predictable sequence of sensory input from the parent, from the family, from the environment seemed to be really important," she said. "At a different time scale, these routines in a family seem to be critical."

Could pediatricians act on unpredictability?

The study authors characterized unpredictability as potentially modifiable. Even when pediatricians cannot change other adversities affecting a family, counseling around consistent routines and caregiver responses could represent one area for future intervention. The study cites family routines as a possible protective factor in circumstances including poverty, parental substance use disorders, and divorce.

Importantly, the current study demonstrated associations rather than showing that introducing routines prevents mental health conditions. The authors concluded that combining unpredictability and ACEs screening could identify children who might otherwise be missed and create opportunities for monitoring and counseling in pediatric primary care.

References

1. Glynn LM, Liu SR, Golden C, et al. Unpredictability is a childhood adversity that contributes to mental health problems. Nat Ment Health. 2026;4:1219-1226. doi:10.1038/s44220-026-00681-x.

2. University of California - Irvine. UC Irvine-led study links unpredictability in early years to elevated mental health risk. Eurekalert. July 21, 2026. Accessed September 18, 2026. https://www.eurekalert.org/news-releases/1136772