Speech and language development is a useful initial indicator of a child's overall development and cognitive ability. Identification of children at risk for delay may lead to interventions, increasing chances for improvement. However, screening for speech and language delay is not widely practiced in primary care.
To determine the strengths and limits of evidence about the effectiveness of selecting, testing, and managing children with potential speech and language delay in the course of routine primary care. Key questions examined a chain of evidence about the accuracy and feasibility of screening children age 5 years and younger in primary care settings, role of risk factors in selecting children for screening, effectiveness of interventions for children identified with speech and language delay, and adverse effects of screening and interventions.
Relevant studies were identified from multiple searches of MEDLINE, PsycINFO, and CINAHL (1966 to November 19, 2004). Additional articles were obtained from recent systematic reviews, reference lists of pertinent studies, reviews, editorials, and websites, and by consulting experts.
Eligible studies had English-language abstracts, were applicable to U.S. clinical practice, and provided primary data relevant to key questions. Studies of children with previously diagnosed conditions known to cause speech and language delay were not included. Only randomized controlled trials were considered for examining the effectiveness of interventions. Studies with speech and language outcomes as well as non speech and language health and functional outcomes were included.
Data were extracted from each study and entered into evidence tables.
Studies were summarized by descriptive methods and rated for quality using criteria developed by the USPSTF. A large descriptive literature of potential risk factors for speech and language delay in children is heterogeneous and results are inconsistent. A list of specific risk factors to guide primary care physicians in selective screening has not been developed or tested. The most consistently reported risk factors include a family history of speech and language delay and learning difficulties, male sex, and perinatal factors. A total of 44 studies about evaluations taking 30 minutes or less to administer that could be administered in a primary care setting were considered to have potential for screening purposes. Studies included many different instruments, there were no accepted gold standards or referral criteria, and few studies compared the performance of 2 or more tests. Studies utilizing evaluations taking 10 minutes or less and rated good to fair in quality reported wide ranges of sensitivity and specificity when compared to reference standards (sensitivity 17% to 100%; specificity 45% to 100%). Studies did not provide enough information to determine how accuracy varied by age, setting, or administrator. Fourteen good and fair-quality randomized controlled trials of interventions reported significantly improved speech and language outcomes compared to control groups. Improvement was demonstrated in several domains including articulation, phonology, expressive language, receptive language, lexical acquisition, and syntax among children in all age groups studied and across multiple therapeutic settings. Improvement in other functional outcomes, such as socialization skills, self-esteem, and improved play themes, were demonstrated in some, but not all, of the 4 studies measuring them. In general, studies of interventions were small, heterogeneous, may be subject to plateau effects, and reported short-term outcomes based on various instruments and measures. As a result, long-term outcomes are not known, interventions could not be directly compared, and generalizability is questionable.
Use of risk factors to guide selective screening is not supported by studies. Several aspects of screening have been inadequately studied to determine optimal methods including what instrument to use, what age to screen, and what interval is most useful. Trials of interventions demonstrate improvement in some outcome measures, but conclusions and generalizability are limited. Data are not available addressing other key issues including the effectiveness of screening in primary care settings, role of enhanced surveillance by primary care physicians prior to referral for diagnostic evaluation, non speech and language and long-term benefits of interventions, adverse effects of screening and interventions, and cost.
speech and language delay, preschool children, screening
