Am Fam Physician. 2006;73(9):1605-1610
This statement summarizes the U.S. Preventive Services Task Force (USPSTF) recommendations on screening for speech and language delay in preschool children and the supporting scientific evidence. Explanations of the ratings and of the strength of overall evidence are given in Table 1 and Table 2, respectively. The complete information on which this statement is based, including evidence tables and references, is included in the evidence synthesis1 on this topic, which is available on the USPSTF Web site athttp://www.uspreventiveservicestaskforce.org. The recommendation also is posted on the Web site of the National Guideline Clearinghouse athttp://www.guideline.gov.
The USPSTF grades its recommendations according to one of five classifications (A, B, C, D, or I) reflecting the strength of evidence and magnitude of net benefit (benefits minus harms). | |
A. | The USPSTF strongly recommends that clinicians provide [the service] to eligible patients.The USPSTF found good evidence that [the service] improves important health outcomes and concludes that benefits substantially outweigh harms. |
B. | The USPSTF recommends that clinicians provide [the service] to eligible patients.The USPSTF found at least fair evidence that [the service] improves important health outcomes and concludes that benefits outweigh harms. |
C. | The USPSTF makes no recommendation for or against routine provision of [the service].The USPSTF found at least fair evidence that [the service] can improve health outcomes but concludes that the balance of benefits and harms is too close to justify a general recommendation. |
D. | The USPSTF recommends against routinely providing [the service] to asymptomatic patients.The USPSTF found at least fair evidence that [the service] is ineffective or that harms outweigh benefits. |
I. | The USPSTF concludes that the evidence is insufficient to recommend for or against routinely providing [the service].Evidence that [the service] is effective is lacking, of poor quality, or conflicting, and the balance of benefits and harms cannot be determined. |
The USPSTF grades the quality of the overall evidence for a service on a three-point scale (good, fair, or poor). | |
Good: | Evidence includes consistent results from well-designed, well-conducted studies in representative populations that directly assess effects on health outcomes. |
Fair: | Evidence is sufficient to determine effects on health outcomes, but the strength of the evidence is limited by the number, quality, or consistency of the individual studies; generalizability to routine practice; or indirect nature of the evidence on health outcomes. |
Poor: | Evidence is insufficient to assess the effects on health outcomes because of limited number or power of studies, important flaws in their design or conduct, gaps in the chain of evidence, or lack of information on important health outcomes. |
Summary of Recommendations
The USPSTF concludes that the evidence is insufficient to recommend for or against routine use of brief, formal screening instruments in primary care to detect speech and language delay in children up to five years of age.I recommendation.
Speech and language delay affects 5 to 8 percent of preschool children, often persists into the school years, and may be associated with lowered school performance and psychosocial problems. The USPSTF found insufficient evidence that brief, formal screening instruments that are suitable for use in primary care for assessing speech and language development can accurately identify children who would benefit from further evaluation and intervention. Fair evidence suggests that interventions can improve the results of short-term assessments of speech and language skills; however, no studies have assessed long-term outcomes. Furthermore, no studies have assessed any additional benefits that may be gained by treating children identified through brief, formal screening who would not be identified by addressing clinical or parental concerns. No studies have addressed the potential harms of screening or interventions for speech and language delays, such as labeling, parental anxiety, or unnecessary evaluation and intervention. Thus, the USPSTF could not determine the balance of benefits and harms of using brief, formal screening instruments to screen for speech and language delay in the primary care setting.
Clinical Considerations
It is the responsibility of primary care physicians to seek and address parents' concerns and children's obvious speech and language delays despite the lack of evidence to support screening with brief, formal instruments. Speech and language development is considered a useful early indicator of a child's overall development and cognitive ability, and clinical and parental concerns are important modes of identifying children with speech and language delays. Early identification of children with developmental delay (i.e., lateness in achieving milestones) or developmental disabilities (i.e., chronic conditions that result from mental or physical impairments), such as marked hearing deficits, may lead to intervention and family assistance at a young age, when chances for improvement may be best.
Specific groups of children who already have been identified as being at higher-than-average risk of speech and language delay, including children with other medical problems such as hearing deficits or craniofacial abnormalities, are not considered in this recommendation. The results of studies of other risk factors are inconsistent, so the USPSTF was unable to develop a list of specific risk factors to guide primary care providers in selective screening. The most consistently reported risk factors, however, include a family history of speech and language delay, male sex, and perinatal factors such as prematurity and low birth weight. Other risk factors reported less consistently include levels of parental education, specific childhood illnesses, birth order, and larger family size.
Discussion
Speech and language development in children is a dynamic process. Speech refers to the mechanics of oral communication; language encompasses the understanding, processing, and production of communication.2 Speech problems may include stuttering or dysfluency, articulation disorders, or unusual voice quality. Several types of speech and language delay and disorders have been described, although the terms used to describe them vary.2 Expressive language delay may exist without receptive language delay, but they often co-occur in children. Some children also have disordered language. These language problems can involve difficulty with grammar (i.e., syntax); words or vocabulary (i.e., semantics); the rules and system for speech sound production (i.e., phonology); units of word meaning (i.e., morphology); and the use of language, particularly in social contexts (i.e., pragmatics). Language and speech problems can exist together or separately.
Reported prevalence rates for speech and language delay vary widely. For children 2 to 4.5 years of age, studies that evaluated combined speech and language delay have reported prevalence rates of 5 to 8 percent, and studies of language delay alone have reported prevalence rates of 2.3 to 19.0 percent. Untreated speech and language delay in children younger than five years has shown variable persistence rates, with most studies reporting 40 to 60 percent.1 Certain congenital conditions such as hearing deficits or craniofacial abnormalities commonly are associated with speech and language delays. Other risk factors that may be associated with speech and language delay include prematurity, family history, male sex, socioeconomic factors, and other developmental delays. However, studies of risk factors have inconsistent results. Children five years or younger whose speech and language delays are untreated may exhibit diminished reading skills in grade school, poor verbal and spelling skills, behavior problems, and impaired psychosocial adjustment. In turn, these problems may lead to overall academic underachievement and a lower intelligence quotient that may persist into young adulthood.1 It is unknown how persistent these problems are.
The USPSTF evaluated the evidence published between 1966 and 2004 to determine the benefits and potential harms of using brief, formal screening instruments for speech and language delay during routine primary care visits. The USPSTF focused on studies of children five years or younger and not diagnosed with conditions associated with speech and language delay. They also limited the evidence review to techniques that take 10 minutes or less to complete and that could be administered in a primary care setting by nonspecialists. The USPSTF found no studies that addressed the overarching question of whether screening for speech and language delay with brief, formal instruments results in improved speech, language, and other non–speech-and-language outcomes. The USPSTF then reviewed the literature for other chains of evidence linking such screening (i.e., the accuracy of screening tests, efficacy of treatments, and harms) to improved health outcomes.
Brief, formal screening instruments, which take 10 minutes or less to administer, could offer a reasonable and standardized approach to screening for speech and language delay in primary care settings. However, screening with such a tool must be followed with a more thorough diagnostic evaluation before implementing an appropriate intervention.
Research on the test characteristics of brief, formal screening instruments has a number of limitations. Some of the research is not generally accessible and is available only in manuals that must be purchased. Most studies lack an accepted gold standard of accuracy for the screening instrument or referral criteria; therefore, various reference standards (e.g., clinical judgment, other instruments) have been used to estimate sensitivities and specificities of brief, formal instruments. Despite extensive literature evaluating a wide variety of instruments, the optimal method of testing has not been established. Most studies have provided insufficient information on variations in accuracy of testing results depending on the child's age, the setting used for the screening, or the administrator of the tests. Few studies compared the performance of two or more tests, compared a single screening technique across different populations of children, or measured long-term outcomes (i.e., more than six months); many studies have evaluated screening instruments that were designed for diagnostic assessment rather than screening.
Studies of good or fair quality that evaluated brief, formal screening instruments have shown that such instruments vary widely in their ability to accurately identify children with speech and language delay. Ten fair- or good-quality studies3–11 conducted in children younger than two years indicated that the instruments studied demonstrate sensitivity ranging from 22 to 97 percent and specificity ranging from 66 to 97 percent. In four fair- or good-quality studies3,4,7,8 conducted in children younger than two years of age, sensitivity and specificity of the Early Language Milestone Scale,3 the Language Development Survey,7,8 and the Clinical Linguistic and Auditory Milestone Scale4 were 80 percent or more. These instruments assess areas such as auditory expressive and receptive skills, vocabulary, and other language skills. In children two to three years of age, eight fair- or good-quality studies12–22 demonstrated sensitivity from 17 to 100 percent and specificity from 45 to 100 percent. The two studies that evaluated the Levett-Muir Language Screening Test19 and the Screening Kit of Language Development,15 both of which assess vocabulary and comprehension, found sensitivity and specificity of 80 percent or more. The three fair-quality studies15,23,24 of screening instruments in children three to five years of age reported sensitivity ranging from 57 to 100 percent and specificity ranging from 80 to 95 percent. Sensitivity and specificity was more than 80 percent using the Screening Kit of Language Development in children three to five years of age.15
Studies have evaluated the effects of individual or group interventions that were directed by physicians and/or parents focusing on specific speech and language domains. These domains included expressive and receptive language, articulation, phonology, and syntax. Interventions were short term, commonly lasting from three to six months, and took place in speech and language specialty clinics, community clinics, homes, schools, and other sites. Outcomes were measured by subjective reports from parents and by scores on standardized instruments.
No randomized control trials (RCTs) were found that focused exclusively on interventions in children younger than two years. However, one good-quality RCT compared 12 months of a physician-directed speech and language intervention to 12 months of “watchful waiting” in children 18 to 42 months of age who had expressive, receptive, or phonologic impairments.25 Only one outcome measure, receptive auditory comprehension, showed significant benefit (P < .025) as a result of the intervention used.25 One good-quality and six fair-quality RCTs evaluated speech and language interventions for children two to three years of age.26 These studies reported improvement on a variety of speech and language domains, including physician-directed treatment to improve expressive and receptive language delay, parent-directed therapy to improve expressive delay, and physician-directed therapy to improve receptive auditory comprehension. In three fair-quality studies, there were no differences in results between groups receiving physician-directed expressive or receptive language therapy, parent-directed expressive or receptive therapy, or parent-directed phonology treatment.1
Seven fair-quality RCTs examined speech and language interventions for children three to five years of age.26 Five fair-quality studies reported significant improvements in the speech and language skills of the children three to five years of age who had received interventions compared with controls, whereas two of the fair-quality studies reported no differences. Both group-based interventions and physician-directed interventions improved expressive and receptive competencies such as expression scores or increased vocabulary.26 The RCTs that demonstrated improved speech and language outcomes had several limitations, such as small sample size; failure to consider potential confounders; the reporting of short-term outcomes; and heterogeneous methods of assessment, intervention, and outcome measurement. The lack of long-term outcomes, comparison data, and generalizability limits conclusions about the effectiveness of interventions.
Improvement in nonspeech and language outcomes was shown in three fair- to poor-quality RCTs.26 However, the interventions and outcomes varied across the studies and lacked appropriate comparison cohorts. Increased toddler socialization skills, improved child self-esteem, and improved play themes were reported for children in these intervention groups. Improved parent-related functional outcomes included decreased stress and increased positive feelings toward their children. One good-quality study26 demonstrated no significant treatment effect for the outcomes of well-being, levels of play and attention, and socialization skills.
No studies have addressed the harms of screening and interventions for speech and language delay in children five years or younger. A potential harm of screening includes receiving either a false-positive or false-negative result. False-positive results can erroneously label children with normal speech and language as impaired, potentially leading to anxiety for children and families and the need for further testing and interventions. False-negative results would miss identifying children with impairment, potentially leading to progressive speech and language delay and other long-term effects including communication, social, and academic problems. Potential harms of interventions include time and cost of interventions for physicians, parents, children, and siblings, as well as stigmatization, labeling, and loss of time for play and family activities.
There are several gaps in the research evidence on screening for speech and language delay in children five years or younger. Areas in which more research is needed include: (1) identifying effective brief, formal instruments that can be used in the primary care setting to screen children in this age group; (2) assessing the effect of earlier compared with later interventions on a broad range of health, educational, and social outcomes related to speech and language delay; (3) identifying risk factors that may be helpful in screening for speech and language delay; (4) testing screening strategies in diverse populations to minimize cultural biases; and (5) translating effective, evidence-based screening approaches for use in primary care practices.
Recommendations from Other Groups
The American Academy of Pediatrics (AAP) recommends that all infants and young children receive periodic screening for developmental delays in the primary care setting.27
The AAP's recommendation statement on developmental screening includes discussions on language skills, behavioral problems, and autism and is not solely focused on speech and language delay. The Centers for Disease Control and Prevention (CDC) recommendation also does not focus specifically on speech and language delay but encompasses developmental disabilities (e.g., autism, mental retardation) and delays (e.g., language). The CDC recommendation28 (athttp://www.cdc.gov/ncbddd/child/improve.htm) encourages developmental screening for autism and other developmental delays in primary care settings. The American Speech-Language-Hearing Association recommends that “pediatric speech-language screening be conducted by appropriately credentialed and trained speech-language pathologists.”29