MONDAY, June 27 (HealthDay News) -- Although there's been some improvement in the number of pediatricians checking toddlers for developmental delays, more than half still don't routinely do so, a new study finds.

In 2002, just 23 percent of pediatricians reported always or almost always using one or more standardized developmental screening tools for infants and toddlers up to 35 months of age. By 2009, that number had risen to just under 48 percent, reported the study.

Early detection of developmental issues such as autism or impaired hearing is key to initiating early and effective treatment, experts said.

"There's more and more evidence that starting early intervention can make a big difference in developmental outcomes than if we wait," explained study co-author Dr. Nina Sand-Loud, an assistant professor of pediatrics and a developmental-behavioral pediatrician at Dartmouth-Hitchcock Medical Center and Dartmouth Medical School in Hanover, N.H.

The new study, published in the July issue of Pediatrics, "is a follow-up to a study done in 2002 looking at the number of pediatric providers doing standardized screening on their patients," she said. "At that time, the number was pretty low. But, since that time, a lot of specific recommendations have been made about screening, so we looked to see if there was a change in practice."

Prior research has found that more than 40 percent of parents have at least one or more concerns about their young child's physical, behavioral or social development, according to the study.

The current study included a national, random sample of pediatricians. Almost 900 pediatricians responded in 2002, while 927 responded in 2009.

The researchers asked about a number of standardized screening tests for children under 3 years of age, such as the Denver Developmental Screening Test, Ages & Stages Questionnaires, or whether or not the pediatrician had developed their own checklist to use during well-child visits.

While more than twice as many pediatricians reported in 2009 that they were doing at least one developmental screening than in 2002, more than half still weren't participating in standardized developmental tests.

Time was probably the biggest reason that doctors gave for not doing formal developmental screenings, said Sand-Loud.

Also, some doctors may feel that they can spot any developmental problems by simply watching the child during the visit and talking to the parents, she said. "But that still misses a big portion of kids with developmental delays," Sand-Loud said.

Dr. Andrew Adesman, chief of developmental and behavioral pediatrics at Steven and Alexandra Cohen Children's Medical Center in New Hyde Park, N.Y., agreed. "Even though parental concerns will often help pediatricians identify most children with developmental problems, the goal of developmental screening is also to identify children with less severe, but nonetheless significant developmental delays that may not be recognized by parents or pediatricians without formal screening."

He said that he thinks more pediatricians will soon be using formal developmental screenings. Electronic medical records and recent changes in insurance company reimbursements will likely help more pediatricians add these tests to their practices, he added.

Sand-Loud said current recommendations call for developmental screening at nine, 18 and either 24 or 30 months during well-child visits.

But if parents have any concerns, they should let their pediatrician know, she said.

Parents may notice emerging issues with their children, but may "let others reassure them that it's nothing, or they may rationalize it themselves. But it's worthwhile to be proactive. Your family doctor or pediatrician is a good resource, and families should feel comfortable bringing up developmental concerns," she said, adding, "It's better to go and make sure everything's OK."

More information

Visit the American Academy of Pediatrics' Healthy Children Web site to learn what developmental milestones to expect from a 12 month old baby.