TITLE: Universal, Community-Based Developmental Screening Tools for Children 6 Years and Younger: A Review of Clinical Effectiveness

Transcription

1 TITLE: Universal, Community-Based Developmental Screening Tools for Children 6 Years and Younger: A Review of Clinical Effectiveness DATE: 23 September 2009 CONTEXT AND POLICY ISSUES: Universal, community-based developmental screening tools for children ages 0 to 6 years, or preschool children, can be used to assess whether children are at risk for developmental delay in different domains such as physical, social, cognitive, vision, language, and hearing. 1,2 Developmental screening tools can be used to identify children at risk for specific or general developmental delays. 1,2 Children flagged as at risk for a developmental delay(s) from a screening tool are referred for a formal assessment for diagnosis of developmental delay. 1 Screening tools are not meant to formally assess children and are not intended to be used to provide a diagnosis. 1 The goal of universal developmental screening is to help children with developmental delays receive interventions and support as early as possible. 3-5 Developmental screening may be part of a larger program delivered to the community that includes areas like nutritional status and mental health. 1 Various general developmental screening tools exist, such as the Nipissing District Developmental Screen (NDDS), the Denver Developmental Screening Test II (DDST-II), and the Parent s Evaluation of Developmental Status (PEDS) 6 as well as several domain-specific screening tools such as the Harris Infant Neuromotor Test (HINT) for screening language delay. 3 The NDDS was developed in Ontario to screen for developmental delay in vision, hearing, speech, language, communication, motor, cognitive, self-help, and social or emotional skills. 7 It can be used in children between the ages of 0 and 6 years. The NDDS is a short checklist Disclaimer: The Health Technology Inquiry Service (HTIS) is an information service for those involved in planning and providing health care in Canada. HTIS responses are based on a limited literature search and are not comprehensive, systematic reviews. The intent is to provide a list of sources and a summary of the best evidence on the topic that CADTH could identify using all reasonable efforts within the time allowed. HTIS responses should be considered along with other types of information and health care considerations. The information included in this response is not intended to replace professional medical advice, nor should it be construed as a recommendation for or against the use of a particular health technology. Readers are also cautioned that a lack of good quality evidence does not necessarily mean a lack of effectiveness particularly in the case of new and emerging health technologies, for which little information can be found, but which may in future prove to be effective. While CADTH has taken care in the preparation of the report to ensure that its contents are accurate, complete and up to date, CADTH does not make any guarantee to that effect. CADTH is not liable for any loss or damages resulting from use of the information in the report. Copyright: This report contains CADTH copyright material. It may be copied and used for non-commercial purposes, provided that attribution is given to CADTH. Links: This report may contain links to other information available on the websites of third parties on the Internet. CADTH does not have control over the content of such sites. Use of third party sites is governed by the owners own terms and conditions.

2 requiring the parent to answer yes or no to statements reflecting age-appropriate skills for the child. 8 Thus, the NDDS is designed to flag a developmental area where a child may require additional help to acquire age-appropriate skills. 8 The NDDS is designed to be sensitive to different cultural values in child rearing. 8 Universal, community-based developmental screening tools such as the NDDS are currently used in at least one Canadian health care jurisdiction. 9 Impact on health-related quality of life, cultural adaptability, and over-referrals to professionals may be considerations surrounding the use of universal developmental screening tools. This HTIS report will help determine whether there is evidence to support the use of universal, community-based developmental screening tools for preschool children. RESEARCH QUESTIONS: 1. What is the clinical effectiveness of universal, community-based developmental screening tools in children aged 6 years and younger? 2. What is the clinical effectiveness of the Nipissing District Developmental Screen in children aged 6 years and younger? METHODS: A limited literature search was conducted on key health technology assessment resources, including Medline, PsychInfo, and ERIC all on the Ovid platform, The Cochrane Library (Issue 3, 2009), University of York Centre for Reviews and Dissemination (CRD) databases, ECRI, EuroScan, international health technology agencies, and a focused Internet search. The search was limited to English language articles published between 2004 and August, Filters were applied to limit the retrieval to health technology assessments, systematic reviews, metaanalyses, randomized controlled trials, controlled clinical trials, and observational studies. HTIS reports are organized so that the higher quality evidence is presented first. Therefore, health technology assessment reports, systematic reviews, and meta-analyses are presented first. These are followed by randomized controlled trials, controlled clinical trials, and observational studies. To be included, studies could be of any research design that assessed a universal, communitybased developmental screening tool that: was administered by a non-professional reported outcomes relative to diagnostic accuracy reported additional clinically-relevant outcomes like the influence on referral rates to health care professionals, health-related quality of life, and cultural adaptability. Thus, excluded studies would include studies that validated a screening tool, used screening tools for children already identified as at risk for a disorder or already diagnosed with a disorder like autism, and studies that assessed screening instruments that required administration by trained specialists like speech and language pathologists or psychologists. SUMMARY OF FINDINGS: One relevant systematic review 5 was identified. The authors assessed different universal screening instruments for speech and language delay and found that more research on screening tools was required. Universal, Community-Based Developmental Screening Tools for Children Ages 6 Years and Younger 2

3 Two relevant observational studies 3,4 were also identified. One study 3 published preliminary findings on the NDDS as well as the HINT and concluded that the accuracy of the NDDS varied over gender, age, and developmental domain areas and that the larger community-level outcomes were positive. The second study 4 assessed the NDDS and the authors concluded that the NDDS was most effective at detecting children at risk for severe developmental delays and less effective at detecting children at risk for mild to moderate developmental delays. No relevant health technology assessments, randomized controlled trials, or clinical controlled trials were identified. Appendix 1 contains additional references that may be of interest. Systematic reviews and meta-analyses Nelson et al. 5 published a systematic review in 2006 on universal screening and interventions for children up to five yeas of age for speech and language delay. The authors asked eight key questions regarding screening and interventions for speech and language. The screening questions included whether screening for speech and language delay resulted in improved speech and language and other non-speech and language outcomes, the adverse effects of screening, and whether screening evaluations in the primary care setting accurately identified children for diagnostic evaluation and interventions. To be included in the systematic review, studies had to screen children aged five years or younger without any previous known conditions associated with speech and language delay such as a hearing impairment, use tools that could be administered by non-specialists, use instruments that could be administered within 10 minutes, use instruments applicable to a primary setting, compare the screening tool to a reference standard, and report sensitivity (ability of the test to correctly identify children with developmental delays) and specificity (ability of the test to correctly identify children without developmental delays) or report enough data to allow calculation of sensitivity and specificity. The authors stated that meta-analyses were not performed due to study heterogeneity. Quality of the included 55 studies was assessed by investigators, but it was unclear how the quality assessment was performed. Of the 24 studies identified relevant to screening, six studies used screening instruments that were completed in the child s home or at a preschool and administered either by the child s parent, teacher, or health visitor. The other 18 studies used screening instruments that were completed by trained professionals such as psychologists, speech and language pathologists, and medical students or were administered in a physician s office or health clinic. Three of the six studies assessed children up to two years of age (total of 792 children assessed) and the remaining three studies assessed children between the ages of two and three years (4495 children assessed). These six studies addressed, in part, the question of whether screening accurately identified children for diagnostic evaluation and interventions. No relevant studies were found on the impact of screening for non-speech and language outcomes, the optimal ages and frequency for screening, and the adverse effects of screening. Three studies screened for expressive language delay in children up to two years of age. The sensitivity ranged between 52% and 94% and specificity ranged between 67% and 99%. Three studies screened for language delay between the ages of two and three years. One study screened for expressive language delay, one study screened for expressive and receptive language delay, and one study screened for expressive, receptive language delay and articulation delay. The sensitivity ranged between 31% and 98% and specificity ranged between Universal, Community-Based Developmental Screening Tools for Children Ages 6 Years and Younger 3

4 45% and 97%. Appendix 2 contains more detailed information on details such as screening instruments, reference instruments, and diagnostic accuracy. The authors concluded that optimal screening tools and methods had not been adequately studied including factors such as which screening instrument should be used and the age at which to screen. The authors also stated that there was a lack of evidence regarding adverse effects associated with screening children. All six of the studies were rated as Fair or Good-Fair by the systematic review authors. The quality of a study was rated on several criteria including use of a relevant, credible, reliable reference standard that was interpreted independently of screening test, and sample size. The author s description of study rated as Fair is one that: Evaluates a relevant, available screening test; uses reasonable (although not the best) standard; interprets the reference standard independent of screening test; and has a moderate sample size ( subjects) and a medium spectrum of patients. A study rated as Good is one that: Evaluates a relevant, available screening test; uses a credible reference standard; interprets the reference standard independently of screening test; assesses the reliability of the test; has few or handles indeterminate results in a reasonable manner; and includes a large number (>100) of broadspectrum patients with and without disease. Methodological strengths of the systematic review included the fact that the authors searched three databases for articles, in addition to other methods such as hand searching, searching Web sites, and consulted experts. The eligibility criteria for ordering full articles were provided (for example, studies had to have English language abstracts). Quality was assessed by the authors. The population selected was reasonable for assessing the effectiveness of screening instruments. A methodological weaknesses was that while the authors reported that investigators performed study selection, data extraction, and quality assessment, it was never reported whether this meant two or more reviewers, whether each reviewer did the entire set of work or someone verified specific percentage of one reviewer s work, plus it was never stated how disagreements were resolved. The authors reported that a meta-analysis was not conducted due to heterogeneity but it unclear what method was used to assess heterogeneity. The authors did not report the possible reasons for heterogeneity. Observational studies Goelman along with the Consortium for Health, Intervention, Learning and Development (CHILD) project 3 published a study in 2008 that overviewed a five-year longitudinal program in British Columbia along with the preliminary findings. One of the three programs of the CHILD was specific to using the NDDS as a universal, community-based screening instrument to identify children at risk of developmental delay. In the Goelman report, it was reported that the NDDS was part of a larger government initiative to support early childhood development. The NDDS started was implemented in 2002 in a small town and surrounding rural areas. Goals of the NDDS included early identification of developmental delays, more timely interventions for children with developmental delay, raising parent s awareness, and increasing capacity of families and community to support healthy childhood development. An evaluation of the validity of the NDDS and wider impact on families and community agencies was undertaken. A total sample of 390 children, comprised of ages of four months, 18 months, 36 months to 42 months, and 60 months to 66 months, were evaluated by the NDDS. The reference instruments included the Bayley Scales of Infant Development (2 nd edition), the Stanford Binet (5 th edition), the Peabody Picture Vocabulary Test (3 rd edition), the Universal, Community-Based Developmental Screening Tools for Children Ages 6 Years and Younger 4

5 Devereux Early Childhood Assessment, the Behaviour Assessment System for Children (2 nd edition), and upon kindergarten entrance, a teacher completed the Early Development Instrument that assesses school readiness. The authors stated that the sensitivity and specificity varied by severity of the delay, gender of the child, developmental domain being tested, scoring rule (one flag or two flag indicating a child who is at risk), and the age version of the test (different versions for different ages). No specific sensitivity and specificity rates or other statistics were reported. From the community perspective, the authors reported that the NDDS had a positive impact on community capacity for early identification and supporting healthy childhood development, increasing parent awareness and knowledge of children s developmental milestones and promoting child development, and increasing confidence in parent s ability. The authors reported that there were strengthened relationships between service providers and the community sites that administered the NDDS. The authors also reported that the NDDS led to a more integrated and efficient referral process. No data collection methods or descriptive or inferential statistics performed were reported for the community outcomes. The authors concluded that the NDDS did not perform equally well over ages, gender, and developmental domains. The authors also concluded that there are community benefits from using the NDDS.The authors did not report much detail on methodology of the study. For example, sample sizes, attrition, or data collection methods were not reported. In 2004, Dahinten and Ford 4 published a validation study for the NDDS for infants and toddlers. The authors recruited participants from an urban area in British Columbia through advertisements in various local venues such as supermarkets, libraries, and preschools. Of the 120 participants, two were excluded due to fatigue or illness accounting for failure to complete the assessment(s). Of the 118 children, 38 were four months of age, 40 were 18 months of age, and 40 were 24 months of age. Overall, 27% of the children were from low-income cut-off families, 8% had single parent home, 14% of the children s mothers were teenagers, and 72% of the children s mothers had more than high school education. Of the children, 54% were female. There were no statistically significant differences between these three age groups for gender of child, whether the child came from a single parent home, whether the child had a teen-aged mother, the education level of the child s mother, or whether the child came from a household with an income below the low income cut-off. The authors compared the NDDS to the Mental Developmental Index (MDI) of the Bayley Scales of Infant Development (2 nd edition) which is commonly used in academic and clinical practice. The MDI gives standard scores with a mean of 100 and standard deviation (SD) of 15. Graduate student research assistants administered the MDI either immediately (86%) after the parent completed the NDDS or within two weeks (14%) of the NDDS completion. A score on the MDI of -1.0 SD, -1.5 SD, and -2.0 SD was interpreted as the presence of mild, moderate, and severe developmental delay, respectively. For the NDDS, two approaches were used. The first is that one answer of no flags the child as at risk for developmental delay, and the second approach requires two answers of no to flag the child as at risk for developmental delay. The authors compared participants who scored mild, moderate, or severe delay on the MDI with the participants who had a single or a double flag on the NDDS. Universal, Community-Based Developmental Screening Tools for Children Ages 6 Years and Younger 5

6 The authors reported sensitivity, specificity, over-referral (proportion of all children who were screened as at risk for developmental delay but do not have a developmental delay), and underreferral (proportion of all children who do not screen as at risk for developmental delay but do have a developmental delay). These numbers are presented in Appendix 3. The sensitivity of the NDDS was 100% for a severe delay and was 50% or less for a mild or moderate delay, for both single and double flag rules on the NDDS. The specificity was above 80% for mild, moderate, and severe delay when a double flag rule was used for the NDDS. The specificity was approximately 70% for mild, moderate, and severe delay when a single flag rule was used for the NDDS. The authors concluded that NDDS had acceptable levels of sensitivity for detecting children with severe developmental delays but that the sensitivity decreased to possibly unacceptable levels for children with mild and moderate developmental delay. This was the case for using the NDDS with a single or double flag rule. When applying the double flag rule for the NDDS, the percentage of over-referrals was 11.9%, 15.3%, and 15.3% for mild, moderate, and severe delay, respectively. The percentage of underreferrals was 7.6%, 2.5%, and 0.0% for mild, moderate, and severe delay, respectively. When the single flag rule was applied to the NDDS, the percentage of over-referral was 25.4%, 30.5%, and 30.5% for mild, moderate and severe delay, respectively. For under-referral, the percentages were 5.9%, 2.5%, and 0.0% for mild, moderate, and severe delay, respectively. The authors pointed out that acceptable validity measures as well as over- and under-referral will depend on what the acceptable levels are for the outcomes as well as the other objectives of the screening program. For example, if the screening tool is used within a larger program that wants to foster family engagement in educational and support activities in relation to child development then perhaps the acceptable levels for validity measures will not be as stringent. The authors concluded that, for children four to 24 months of age, the NDDS was most effective at flagging children at risk for severe developmental delays. This distribution of mild, moderate, and severely delayed children detected by the MDI was similar to the 16%, 7%, and 2.3% distribution that would be expected under the normal distribution upon which the MDI is based. No statistically significant differences were found between age groups, gender, or interaction of age by gender, but the authors cautioned that the lack of statistical difference might be explained by the fact that the sample sizes were not large enough to provide adequate power for this level of investigation. The MDI and the NDDS for this study was administered by graduate students in a research setting. The NDDS would normally be administered by a health care provider in a clinical setting. The graduate students did not discuss any of the items on the NDDS with the parents which may have resulted in more no responses. For example, if the parent did not think the child could pick up a cheerio but could pick up other similar items the parent may have responded no when in fact could have responded yes. This may have affected the specificity. Also, social desirability bias (the parent may have answered in a specific manner because of the awareness that the items are indicators of normal development) may have affected the sensitivity. Limitations In order to produce a reliable report within a strict timeframe, HTIS reports focus on current literature that is English, published, and peer-reviewed. These decisions may impact the Universal, Community-Based Developmental Screening Tools for Children Ages 6 Years and Younger 6

7 literature included and thus, the conclusions of the report. There were few prospective comparative studies identified that reported on universal, community-based developmental screening tools. There were even fewer studies that focused on clinically-relevant outcomes in addition to validity measures. Clinical outcomes could have included the consequences (if any) of too many false positives, and the ability to detect mild, moderate, and severe developmental delay that would have otherwise not been detected through routine medical appointments or parental concern, or any health-related quality of life outcomes for the child screened. Most of the research failed to report demographic details (for example, ethnicity, income levels of household, education level of parents) which limits the ability to generalize the findings. CONCLUSIONS AND IMPLICATIONS FOR DECISION OR POLICY MAKING: Two common factors used to assess validity of a screening tool are sensitivity and specificity of the screening instrument. There are no universal levels of sensitivity or specificity that can be used to determine whether a screening tool is acceptable, however, 70% to 80% are usually considered acceptable sensitivity levels. 10 In the included studies, there was much variability in the sensitivity and specificity percentages depending on the screening instrument used, the reference standard used, the age of the child, and the developmental domain assessed. Given the heterogeneity of studies included, no reliable conclusions regarding the sensitivity and specificity can be made for any specific developmental screening tool. Factors other than sensitivity and specificity rates may be considered when determining whether a universal community-based tool is acceptable. For example, as was the case for one included observational study 3, if the screening tool is part of a larger community-level program, then poorer sensitivity and specificity may be acceptable if larger goals are being met such as raising parent awareness of child development and partnerships between professionals and community centers administering the screening tools. Another factor to consider is the severity of delay that is being flagged on a screening tool as the sensitivity and specificity can vary greatly with this variable. One included observational study 4 concluded that the NDDS provided acceptable sensitivity rates for detecting severe developmental delay in children but not for mild to moderate developmental delay. Another valuable measure is the over-referral and under-referral rates that result from the administration of the screening instrument. This was calculated for one study, 4 however, the decision as to whether the rate is considered acceptable is subjective. No studies addressed the possibility of the developmental screening tool impacting the child s health-related quality of life. No studies were identified that addressed cultural adaptability. There is currently insufficient evidence that can be used to reliably estimate whether universal, community-based developmental screening tools for children aged 0 to 6 years are effective in detecting children at risk for disabilities that would be otherwise missed in the system, whether they cause over-referrals (due to false positives), whether they can affect the health-related quality of life of the child, and whether it is culturally adaptable in Canadian populations. Universal, Community-Based Developmental Screening Tools for Children Ages 6 Years and Younger 7

8 PREPARED BY: Rhonda Boudreau, BA, BEd, MA, Research Officer Ray Banks, AB, MA, MLS, Information Specialist Health Technology Inquiry Service Tel: Universal, Community-Based Developmental Screening Tools for Children Ages 6 Years and Younger 8

9 REFERENCES: 1. First Nations of Quebec and Labrador,Health and Social Services Commission. Maternal child health screening tool project [Internet]. Wendake(QC): The Commission; [cited 2009 Sep 2]. Available from: 2. National Center on Birth Defects and Developmental Disabilities. Facts about developmental screening tools [Internet]. Atlanta: Centers for Disease Control and Prevention; [cited 2009 Sep 2]. Available from: 3. Goelman H, The CHILD Project. Three Complementary Community-Based Approaches to the Early Identification of Young Children at Risk for Developmental Delays/Disorders. Infants Young Child [cited 2009 Aug 19];21(1): Dahinten VS, Ford L. Validation of the Nipissing District Developmental Screen for use with infants and toddlers: working paper [Internet]. Vancouver: Human Early Learning Partnership (HELP); [cited 2009 Sep 2]. Available from: search%20report%20(2004%2011%2015)%20final.pdf 5. Nelson HD, Nygren P, Walker M, Panoscha R. Screening for speech and language delay in preschool children: systematic evidence review for the US Preventive Services Task Force - Interventions. Pediatrics [cited 2009 Sep 2];117(2):e298-e319. Available from: 6. Ringwalt S. Developmental screening and assessment instruments with an emphasis on social and emotional development for young children ages birth through five [systematic review] [Internet]. Chapel Hill: National Early Childhood Technical Assistance Center, University of North Carolina at Chapel Hill; [cited 2009 Sep 2]. Available from: 7. Nipissing District Developmental Screen (NDDS). Nipissing District Developmental Screen [Internet]. North Bay: NDDS [cited 2009 Sep 2]. Available from: 8. Nipissing District Developmental Screen (NDDS). FAQ: frequently asked questions [Internet] [cited 2009 Sep 10]. Available from: 9. Nipissing District Developmental Screen (NDDS). Nipissing District Developmental Screen [Internet]. North Bay: NDDS [cited 2009 Sep 2]. Available from: Westerlund M, Berglund E, Eriksson M. Can severely language delayed 3-year-olds be identified at 18 months? Evaluation of a screening version of the MacArthur-Bates Communicative Development Inventories. J Speech Lang Hear Res Apr;49(2): Universal, Community-Based Developmental Screening Tools for Children Ages 6 Years and Younger 9

10 APPENDIX 1: ADDITIONAL REFERENCES The following list presents two references to articles that provide compilations of developmental screening instruments for preschool children. The third reference is a PhD dissertation on screening preschool children but is not published through a peer-review journal. 1. Ringwalt S. Developmental screening and assessment instruments with an emphasis on social and emotional development for young children ages birth through five [systematic review] [Internet]. Chapel Hill: National Early Childhood Technical Assistance Center, University of North Carolina at Chapel Hill; [cited 2009 Sep 2]. Available from: 2. Sosna T, Mastergeorge A. Compendium of screening tools for early childhood socialemotional development [Internet]. Sacramento: First 5 California Special Needs Project; [cited 2009 Sep 2]. First 5 California special Needs project; Available: df 3. Wells CD. Identifying preschool students in need of early intervention [dissertation]. United States: University of Southern Mississippi; Universal, Community-Based Developmental Screening Tools for Children Ages 6 Years and Younger 10

11 APPENDIX 2: SUMMARY OF SYSTEMATIC REVIEW ON SCREENING FOR SPEECH AND LANGUAGE DELAY Table 1. Summary of Six Relevant Studies Included in the Systematic Review on Screening for Speech and Language Delay 5 Instrument Used Reference Instrument Studies Assessing Children up to Age of Two Years Language Development Language Development Survey [assesses Survey expressive vocabulary by having the parent select the words, from a list of 310 words that their child has spoken and also had the parent describe word combinations (2 or more words) that the child had spoken] Clinical judgment -two blinded, independent judgments from two speech and language pathologists -supported by one of three standardized measures falling below -1.0 standard deviation as the reference standard Clinical judgment -two blinded, independent judgments from two speech and language pathologists -supported by one of three standardized measures falling below -1.0 standard deviation as the reference standard Administrator and Setting Sensitivity 91% 83% (age 2) and 67% (age 3)* Language Development Survey Bayley Scales of Infant Development, Stanford- Binet, and Reynell Developmental Language Scales Parent, home Parent, home Parent and research assistant, home Delay 1 70% (Bayley) 94% (Reynell) 52% (Binet) Delay 2 75% (Bayley) 77% (Reynell) 56% (Binet) Delay 3 80% (Bayley) 67% (Reynell) 64% (Binet) Specificity 87% 97% (age 2) and 93%, (age 3)* Quality Rating Good-Fair Fair Fair Delay 1 99% (Bayley) 94% (Reynell) 98%, (Binet) Delay 2 96% (Bayley) 77% (Reynell) 95% (Binet) Delay 3 94% (Bayley) 67% (Reynell) 94% (Binet) Universal, Community-Based Developmental Screening Tools for Children Ages 6 Years and Younger 11

12 Studies Assessing Children Between the Ages of Two and Three Years Instrument Used The Parent Language Checklist -12-item questionnaire -receptive and expressive language ability Fluharty Preschool Speech and Language Screening Test -35 items; identification of common objects, nonverbal responses to sentences, and imitation of one-sentence picture descriptions. -expressive language, receptive language, and articulation Hackney Early Language Screening Test -20-item test that assess comprehension over four tasks and expression over three tasks -expressive vocabulary Reference Instrument Clinical judgment Arizona Articulation Proficiency Scale Revised, Test of Language Development Primary Test for Auditory Comprehension of Language Revised, Templin-Darley Test of Articulation Screener and Setting Sensitivity 87% Study 1 43% for speech and language, 74% for speech, and 38% for language Study 2 31% for speech and language, 43% for speech, and 17% for language Reynell Developmental Language Scales Parent, home Child s teacher, preschool Health visitor, home Specificity 45% Study 1 82% for speech and language, 96% for speech, and 85% for language. Study 2 93% for speech and language, 93% for speech, and 97% for language. Quality Rating Good Fair Good-Fair *Unclear why this was reported since the category was children up to two years old; =definitions of delay 1, delay 2, and delay 3 not reported; possibly corresponds to standard deviations away from the norm. Bayley=Bayley Scales of Infant Development (unknown edition); Binet= the Stanford Binet (unknown edition); Reynell=Reynell Developmental Language Scales 98% 69% Universal, Community-Based Developmental Screening Tools for Children Ages 6 Years and Younger 12

13 APPENDIX 3: SUMMARY TABLE FOR DAHINTEN AND FORD S 4 OBSERVATIONAL STUDY Table 1. Validation Measures of One Flag on NDDS Compared to MDS Standard Deviation -1.5 Standard Deviation -2.0 Standard Deviation Sensitivity Specificity Over-referral Under-referral 56.3% 70.6% 25.4% 5.9% 50.0% 67.9% 30.5% 2.5% 100.0% 68.7% 30.5% 0.0% SD=standard deviation, sensitivity=ability of the test to correctly identify children with developmental delays, specificity=ability of the test to correctly identify children without developmental delays), over-referral=proportion of all children who were screen as at risk for developmental delay but do not have a developmental delay, under-referral=proportion of all children who do not screen as at risk for developmental delay but do have a developmental delay Table 2. Validation Measures of Two Flags on NDDS Compared to MDS Standard Deviation -1.5 Standard Deviation -2.0 Standard Deviation Sensitivity Specificity Over-referral Under-referral 43.8% 86.3% 11.9% 7.6% 50.0% 83.9% 15.3% 2.5% 100.0% 84.3% 14.3% 15.3% SD=standard deviation, sensitivity=ability of the test to correctly identify children with developmental delays, specificity=ability of the test to correctly identify children without developmental delays), over-referral=proportion of all children who were screen as at risk for developmental delay but do not have a developmental delay, under-referral=proportion of all children who do not screen as at risk for developmental delay but do have a developmental delay Universal, Community-Based Developmental Screening Tools for Children Ages 6 Years and Younger 13