The development of language in children is like the canary in the coal mine – problems of genetics, medical conditions, and environment all can cause it to go awry. Whatever the cause, it is very important to make sure a child with a problem in this area gets prompt assistance, because how speech and language progress also affects many aspects of the child’s success in life and what it is like to parent them.

Some of the factors known to put a child at risk for delays or deviations in speech and language development include prematurity and low birth weight; genetic conditions such as Down syndrome; physical problems such as cerebral palsy or seizure disorders; hearing impairment; and, as usual, being a boy. The most common reason for delayed language is general delay or intellectual disability. A family history of speech and language disorders also adds to the risk, and one single gene defect has even been found for a few of these. Eight percent of young children have been estimated to have a delay in speech or language. The vast majority of them have no specific risk factors.

The “language environment” of the home is critical to language learning. Compared with high-income families, parents on welfare say one-third as many words to their children and working-class parents say one-half as many in the first 3 years. Because over 85% of a child’s words at age 3 years come from words heard from their parents, this is estimated to create a 30-million-word difference between children of high- versus low-income families by age 4 years! In addition, low-income parents provide two discouragements for each one encouragement, in contrast to one correction to six encouragements in high-income homes, with the additional psychological implications.

These sad facts contributed to the creation of the Reach Out and Read program, which I hope you have joined. A free book from the doctor at every checkup visit, some modeling of how to read to the child, and information about the importance of talking with the child are things you can do to emphasize the importance of language stimulation to development and academic success.

Most parents are very motivated by the promise of better school success from better language, but it can seem far away when the child is only 1 year old! A more immediate motivator is the threat of more temper tantrums and noncompliance in children with delayed language. Almost all children with language problems understand more than they can express. When the gap between understanding and speaking is greater, so is the child’s frustration. While a large percentage of children with expressive language problems will “outgrow” them, the pattern of angry reactivity and difficult parent child interactions may continue. This is a good reason to discuss promoting language but to also suggest Baby Signs ( starting in the first year, especially if communication frustration starts to emerge.

School is where the big impact from language impairments appears. And it is not just the significant association between early language disorders and persistent reading disability and even written language disability that you should worry about and monitor. Children with speech and language disorders, even simply dysarticulation, can be teased, bullied, and rejected socially. As a result, children with speech and language deficits experience lower self-esteem, greater discouragement, and sometimes reactive aggression. In addition to identifying these problems and getting treatment for the issues of language, learning, and socio-emotional adjustment, it is important to find nonverbal strengths in the child such as sports or music to give them a social group where they can find success.

Language problems in older children may be subtle and not noticed or complained about by their parents, who may have the same weakness. Even teachers may not connect the student’s poor academic performance to language difficulties because they seem to have “the basics.” If you notice a schoolaged child unable to understand or answer your questions with some sentence complexity, it is important to refer to a speech pathologist for assessment. Although there should be free evaluation and treatment services at the school, the speech pathologist may not be expert at assessing more complex language disorders. In addition, the child’s difficulties may not measure up as “impairing enough” to receive those services, and private services may be needed.

But if you do not feel like a child language expert, you are not alone! Not only were you lucky if you heard one lecture on language development during training, but the younger the child, the less language you are likely to hear from him or her during brief health supervision visits. The parent is probably dominating the conversation (if you are a good listener) trying to have their agenda addressed, and the child is either excited or terrified by your office environment.

The broadband developmental screening now recommended by the American Academy of Pediatrics for all children at 9, 18, and 30 months includes language milestones or parental concern, but these have not been shown to have adequate sensitivity or specificity and will miss many affected children.

Many young children with language disorders are now or will later be on the autism spectrum. The recommended autism-specific screens at 18 and 24-30 months will detect many, but not all, of these children. It is important to realize that the most common reason for a false positive autism screen is language delay, and it deserves follow-up and treatment even though not representing autism.

What should you do given these gaps between need, tools, and knowledge? Of course, collect the general and autism screens as recommended, but also use them when you or the parent have a concern. For children under 2 years, the parent’s report is generally accurate, as expected language is fairly simple. Infants should have different cries and reactions to caregivers in the first 3 months; babble and laugh by 6 months; and imitate sounds as well as recognize a few words by 1 year. While infants typically have 1-2 words by 12 months and two-word combinations by 18 months, as a cutoff they should show 1-2 words by 18 months and either 50 words or 2 words together by 24 months. Listening to a child’s spontaneous language is the best gauge of articulation. By age 2 years, we – a stranger to the child – can only expect to understand about 25% of what they say, but by 3 years it should be 66%, and by age 4 years almost 100%.

Gestures are an important aspect of communication. Use of gestures such as raising arms to be picked up or waving bye-bye by 1 year are typical. Between 1 and 2 years, children should follow your pointing and share their interests by pointing in addition to indicating named pictures and body parts. Deficits in use of gestures should spur a language evaluation and also are part of diagnosing autism, a much more serious and specific condition defined by communication deficits. Most autism screening tools include tapping gestures as well as spoken language.

After 2 years, language assessment has to include more elements than many parents can report easily or you can observe. There is now no formal additional language screening recommendation beyond surveillance, and the general developmental and autism screens. Every state has free child development services that can assess and provide intervention for children 0-3 years if you or the parent has concerns. But you may want to do more to either reassure or clarify the need for and type of referral by using a language-specific tool. The most accurate and practical tools applicable to children 8-35 months are the MacArthur-Bates Communicative Development Inventories ( CDI ) and the Language Development Survey ( LDS ), both parent completed. The LDS assesses based on a list of vocabulary words and examples of phrases, and the CDI has three different forms using vocabulary, gestures, and sentences.

After age 3 years, language is so complex that direct testing of the child is needed. A draft report from the U.S. Preventive Services Task Force in November 2014 presents a review of all available measures.

The good news is that a variety of approaches to therapy for speech and language disorders in young children are effective in reducing impairment. The most effective ones involve the parents in learning what communication skills to observe, stimulate, and reinforce, and have an adequate number of total hours of intervention spread over several months.

As for all children and youth with special health care needs, we have the responsibility to detect, monitor, refer, track, and support families of children with speech and language disorders to assure their best outcomes. Whatever the cause, improving the communication abilities of the child can make a big difference to many aspects of their lives.

Dr. Howard is an assistant professor of pediatrics at the Johns Hopkins University School of Medicine, Baltimore, and creator of CHADIS ( ). She has no other relevant disclosures. Dr. Howard’s contribution to this publication was as a paid expert to Frontline. E-mail her at .