4 Separate Papers. Write a one-page review, single spaced of each of the assigned readings. Article responses should include a description of the article itself and a reaction to the article. I will a

For the total group, the rate of development during intervention was significantly greater than the rate of development at pretest across all developmental domains of the CADS. This finding was true for five of the six domains when analyses were limited to children with Down syn- drome. On the BDI, results were available on 75 of the 194 children, 45 of whom had Down syndrome. Significant differences were found on six of the seven domains. When the rates of the 45 children with Down syn- drome were analyzed, significantly higher rates were found on three of the seven domains. These results support the effectiveness of one of the original model programs of the Handicapped Children's Early Education Program.

As states continue to make decisions on the implementation of Public Law 99-457, it is important that researchers and service TECSE 11(1), 56-68 (1991) © PRO-ED Inc. at FLORIDA INTERNATIONAL UNIV on June 17, 2015 tec.sagepub.com Downloaded from MODEL PRESCHOOL PROGRAM, 57 providers make available to decision makers information on what has been learned about effective models and practices for early intervention.

In 1968 Congress passed the Handicapped Children's Early Educa- tion Assistance Act, which funded 24 experimental early intervention programs to develop curricula and model programs that others might be able to replicate. These original programs were remarkably suc- cessful and have provided generations of subsequent programs with exemplary models of quality intervention. This article describes one of these original models and shares outcomes from the replication sites of this program.

The Model Preschool Program (MPP) for Children with Down Syndrome and Other Developmental Delays was one of the original centers funded under the above-referenced act. The MPP began in 1971 as a program of the Experimental Education Unit, Child Develop- ment and Mental Retardation Center, at the University of Washing- ton. In the first few years the MPP focused entirely on children with Down syndrome; however, this changed quickly as it became apparent that the MPP could be used effectively with other developmentally delayed children.

Four objectives guided the services of the MPP. First was the emphasis on planning and implementing specific programs to increase the children's rate of development in six skill areas: gross and fine motor, cognition, receptive and expressive communication, and social/ self-help. A test-teach-test model using a curriculum-based assessment tool served as the core of this systematic and individualized instruc- tion (assessment, setting of goals and objectives, programming, imple- mentation, and evaluation). In all areas of instruction, children were guided through the stages of learning, including acquisition, fluency, transfer, and generalization of basic skills.

A second objective required the involvement of the parents in the children's instruction. When possible, parents attended their children's classes, mastered the instructional strategies that were being imple- mented in the classrooms, and provided further instruction using the same developmental, academic, and behavioral management techniques that were being used successfully in the school. Decades later, parents attributed much of their child's success to the continuity between what was happening in the program and the carryover implemented by the family.

A third objective for this program was to provide a site for qual- ity training for university students and others in the field who wanted to study these principles. This objective, focusing on professional train- ing, led to the successful establishment of numerous outreach sites of at FLORIDA INTERNATIONAL UNIV on June 17, 2015 tec.sagepub.com Downloaded from 58, TOPICS IIM EARLY CHILDHOOD SPECIAL EDUCATION 11:1 the MPP throughout the United States and in many foreign countries. The replication of this project was the fourth objective of this program.

In 1975 the MPP became one of the first early intervention pro- grams for young children with disabilities to be validated by the Joint Dissemination and Review Panel, now known as the Program Effec- tiveness Panel. As more sites asked to replicate the MPP, the developers found that the program could be successfully implemented with chil- dren and in sites that differed considerably from those served in the original model. The MPP was implemented in large and small schools, with children from birth through age 12, in programs that were self- contained and integrated (see Fewell &C Oelwein, 1990), in classes that had different child-to-teacher ratios, in urban and rural settings, with certified, advanced degree teachers and paraprofessionals, in public and private sites, and in programs that varied in the length of time in instruction, number of days of instruction, and length of the academic school year. What did not differ were the standards of implementation required of all sites if they were to be named as a cer- tified outreach site. Staff in all of these sites had to master the cur- riculum and the implementation of the MPP. They were evaluated through on-site observations by trainers from the MPP. Outreach sites that successfully met program standards, and continued the model program activities for at least 2 years, could apply to be "turnkey" sites and train others in the model. This plan, which took a program developed in the far northwest corner of the United States and expanded it throughout the country, proved to be successful and cost-effective.

In this article, we report developmental outcomes of children in the United States who participated in outreach sites of the MPP pro- gram. This study was part of a larger study investigating the impact of this program on children with disabilities in outreach sites through- out the world. We addressed three problems that have been cited as concerns in previous early intervention studies (Dunst &C Rheingrover, 1981; Oelwein, Fewell, & Pruess, 1985; Odom & Fewell, 1983; Smith, 1986). First, the same intervention program was provided to a large sample of young children with disabilities. Second, sites were located in many different states, yet all were certified and monitored. Third, a sample of 75 of the 194 children were assessed on a nation- ally standardized test that included the domains of the curriculum- based assessment measure, the results of which could be used to provide the validation of the outcomes of the curriculum-based measure. at FLORIDA INTERNATIONAL UNIV on June 17, 2015 tec.sagepub.com Downloaded from MODEL PRESCHOOL PROGRAM, 59 Method Subjects Subjects for this study were 194 children with disabilities, all enrolled in outreach sites of the MPP. Ninety-two of the children had Down syndrome. The major handicapping conditions of the other chil- dren in this study were mental retardation from causes other than Down syndrome, severe communication disorders, behavior disorders, neurological impairments, orthopedic handicaps, and multiple handi- caps. In the total group were 115 males and 79 females whose mean chronological age at posttest was 63 months, with a range of 8 to 144 months. In the group of children with Down syndrome were 47 males and 45 females with a mean age of 57 months and a range of 8 to 144 months. Intervention Sites All of the subjects in this study were served in sites that had offi- cially adopted the MPP. Information about the 14 sites represented in this study is reported in Table 1. Sites differed in the number of weeks or months of intervention, the number of days during each week of intervention, and the length of day in which the model was imple-mented. The sites also differed in the total number of minutes that children were placed in settings with peers without known disabili- ties. In a recent article (Fewell & Oelwein, 1990), we reported that the time (average number of minutes per week) of integration in the classrooms was not a factor strong enough to account for significant differences in the intervention rates of development of the students. Instrument Staff at all sites were provided training on the assessment mea- sure used in this program, the Classroom Assessment of Development Skills (CADS) (Oelwein, Fewell, & Pruess, 1988), or on the earlier /ersion of the test. The CADS was a new version of the Developmen- :al Sequence Performance Inventory (Oelwein, Fewell, & Pruess, at FLORIDA INTERNATIONAL UNIV on June 17, 2015 tec.sagepub.com Downloaded from 60, TOPICS IN EARLY CHILDHOOD SPECIAL EDUCATION 11:1 Table 1. Sites and School Characteristics City, state Coral Gables, FL Chehalis, WA Sumner, WA Vancouver, WA Columbus, GA Fayetteville, GA King wood, TX Gering, NE Alcorn, MS Naches, WA Grandview, WA Eureka, CA Ada, OK Santa Cruz, CA Note. S = suburban location; center. n 34 22 29 11 17 19 8 5 6 3 8 9 16 7 R = rural location; Geographic area S R R S S R S R R R R R R S P = private school; PS = = public school; DC School type P PS DC DC P/PS DC P PS PS PS PS PS PS PS = developmental 1984), a test that had been used in the earlier phases of the MPP. There were no administrative differences in the two instruments; however, all changes were explained to staff at the sites. The CADS is a curriculum-based assessment that includes six developmental domains (gross and fine motor, cognitive, receptive and expressive communication, social/self-help) and covers the age range from birth to 8 years. The test includes 288 items of equal weight spread over seven developmental levels. Two scores, a Developmen- tal Age Score and a Developmental Quotient Score, are obtained for each of the six developmental domains. The CADS serves as an assess- ment tool and as a basis for identifying objectives for instruction. Once students attain objectives, subsequent objectives are set from the CADS.

During the development of the CADS, several investigations were conducted. The CADS was field tested in outreach sites in 1985-86, revised in the summer of 1986, and used to measure program effective- ness for the 1986-87 school year. Correlations between the subtests of the CADS and the subtests of the Battelle Developmental Inven- tory (BDI) (Newborg, Stock, Wnek, Guidubaldi, & Svinicki, 1984) ranged from .80 (personal-social/self-help) to .92 (cognitive), and were highly significant. Procedure All subjects were tested in September or when they entered the program, and again in May, June, or September or when they exited at FLORIDA INTERNATIONAL UNIV on June 17, 2015 tec.sagepub.com Downloaded from MODEL PRESCHOOL PROGRAM, 61 the program, if prior to the scheduled posttesting period. The minimum time between testing for all subjects was 3 months and the maximum time was 13 months. The average time between pre- and posttesting was 9 months.

In addition to the CADS, staff at five sites (Coral Gables, Colum- bus, Fayetteville, Kingwood, and Santa Cruz) administered the BDI.

The BDI battery includes the following domains: personal-social, adap- tive, motor (gross and fine), communication (reception and expres- sion), and cognition. The entire battery takes about IV2 to 2 hours.

It is recognized as one of the most frequently given tests in the field today, largely because of the wide age span it covers (birth to 8 years) and because the test covers all domains central to intervention pro- grams (Mott et al., 1986). Data Analysis Data gathered on the CADS and on the BDI were analyzed accord- ing to the procedure recommended by Snyder-McLean (1987) for reporting norm-referenced program evaluation data. After reviewing several widely used procedures, Snyder-McLean recommended a simple procedure comparing a pretest Developmental Quotient with an Inter- vention Developmental Quotient. In this three-step procedure, the rate of development a child demonstrates during intervention (IR) is cal- culated by subtracting the child's Developmental Age (DA) at pretest- ing from age at posttesting and then dividing that difference by the months in intervention. The final step is to test whether significant differences exist between the IR and the developmental rate at pretest (DRP). A series of t tests were used to test these differences across the six domains of the CADS and seven domains of the BDI. Results The results are presented for the total group on the CADS and the BDI and for the group of children with Down syndrome on the same two measures. Table 2 presents the mean IRs, DRPs, differences between IRs and DRPs, standard deviations, and t and p values for the total group. IRs were significantly higher than DRPs in every domain of the CADS. at FLORIDA INTERNATIONAL UNIV on June 17, 2015 tec.sagepub.com Downloaded from 52, TOPICS IN EARLY CHILDHOOD SPECIAL EDUCATION 11:1 fable 2. Difference Between Intervention Rate and Developmental Rate at Pretest on CADS Domains All subjects Domain Gross motor Fine motor Cognitive Communication (receptive) Communication (expressive) Social/self-help n 175 194 193 186 187 191 Mean IR .92 1.09 1.23 1.12 1.11 1.11 SD .733 .847 .733 .789 .837 .844 Mean DRP .66 .67 .68 .64 .54 .68 SD .252 .264 .269 .266 .275 .253 Difference IR/DRP .26 .42 .55 .48 .56 .43 f 4.76 7.07 9.78 8.11 8.93 7.01 P .000 .000 .000 .000 .000 .000 Note. CADS = Classroom Assessment of Developmental Skills; IR = intervention rate; DRP = developmental rate at pretest. Males = 115; females = 79. Mean age at posttest = 63 mos.; range = 8 to 144 mos. Mean interval, pre- to posttest = 9 mos.; range = 3 to 13 mos. BDI results for the total group [n = 75) are reported in Table 3. Significantly different scores were found in six of the seven develop- mental domains. The IR for gross motor development was higher than the DRP; however, this difference failed to reach an acceptable level of significance. Table 4 presents for the Down syndrome subgroup the same information as presented in Table 2. In five of the six domains of the CADS, IRs were significantly higher than DRPs. In the area of gross motor development, the IRs were not significantly different from DRPs. Table 5 presents the results on the BDI for the children with Down syndrome. There were significant differences between the IRs and the DRPs on three (cognitive, personal-social, and adaptive) of the seven tests. On the remaining four tests, there were no signifi- cant differences between the two rates. Discussion The purpose of this study was to investigate the effectiveness of the model program in increasing the mean rates of developmental skill acquisition in young children with disabilities. Two additional objec- tives were important in this study: (1) to investigate the use of a new edition of the model program's earlier test and curriculum, and (2) to determine whether program effectiveness would be reflected in a nation- ally standardized test of early child development. at FLORIDA INTERNATIONAL UNIV on June 17, 2015 tec.sagepub.com Downloaded from MODEL PRESCHOOL PROGRAM, 63 Table 3. Difference Between Intervention Rate and Developmental Rate on BDI Domains All subjects Domain Gross motor Fine motor Cognitive Communication (receptive) Communication (expressive) Personal/social Adaptive n 75 75 75 75 75 75 75 Mean IR .74 .92 .82 .72 .70 .98 .94 SD .966 1.279 .616 .907 .972 .903 .768 Mean DRP .54 .57 .49 .43 .44 .44 .41 SD .164 .190 .207 .220 .194 .222 .205 Difference IR/DRP .20 .35 .33 .29 .26 .54 .54 t 1.70 2.28 4.42 2.54 2.32 5.01 5.81 P .093 .025 .000 .013 .023 .000 .000 Note. BDI = Battelle Developmental Inventory; IR = intervention rate; DRP = developmental rate at pretest.

Males = 48; females = 27. Mean age at posttest = 54 mos.; range = 8 to 117 mos. Mean interval, pre- to posttest = 9 mos.; range = 4 to 13 mos. Table 4. Difference Between Intervention Rate and Developmental Rate at Pretest on CADS Domains Down syndrome subjects Domain Gross motor Fine motor Cognitive Communication (receptive) Communication (expressive) Social/self-help n 88 92 92 88 89 90 Mean IR .75 .98 .94 .99 .83 .94 SD .615 .784 .516 .811 .600 .760 Mean DRP .68 .71 .74 .68 .56 .72 SD .229 .247 .262 .210 .220 .212 Difference IR/DRP .06 .27 .21 .31 .28 .22 f .98 3.33 3.30 3.37 3.84 2.76 P .330 .001 .001 .001 .000 .007 Note. CADS = Classroom Assessment of Developmental Skills; IR = intervention rate; DRP = developmental rate at pretest. Males = 47; females = 45. Mean age at posttest = 57 mos.; range = 8 to 144 mos. Mean interval, pre- to posttest = 9 mos.; range = 3 to 13 mos. The results of this study provided evidence that rates of develop- ment in young children with disabilities were significantly higher during intervention than when the children entered the program. These find- ings were true for all subtests of the CADS, and on six of the seven subtests of the nationally standardized test, the BDI. When the analysis was limited to children with Down syndrome, effects were more mixed.

Significantly higher rates of development were found during interven- tion on five of the six subtests of the CADS and on three of the seven subtests of the BDI. at FLORIDA INTERNATIONAL UNIV on June 17, 2015 tec.sagepub.com Downloaded from 64, TOPICS IN EARLY CHILDHOOD SPECIAL EDUCATION 11:1 Table 5. Difference Between Intervention Rate and Developmental Rate at Pretest on BDI Domains Down syndrome subjects Domain Gross motor Fine motor Cognitive Communication (receptive) Communication (expressive) Personal/social Adaptive n 45 45 45 45 45 45 45 Mean IR .73 .66 .63 .48 .39 .93 .79 SD .937 .603 .605 .760 .700 .801 .737 Mean DRP .52 .54 .43 .39 .42 .40 .36 SD .134 .169 .207 .191 .160 .232 .200 Difference IR/DRP .21 .12 .20 .08 -.03 .53 .43 t 1.47 1.21 1.99 .64 -.29 4.31 3.72 P .148 .232 .053 .523 .777 .000 .001 Note. BDI = Battelle Developmental Inventory; IR = intervention rate; DRP = developmental rate at pretest.

Males = 28; females = 17. Mean age at posttest = 55 mos.; range = 8 to 106 mos. Mean interval, pre- to posttest = 9 mos.; range = 4 to 13 mos. It is interesting to note the areas of development in the children with Down syndrome in which developmental rates during interven- tion failed to be significantly different from rates at program entry.

No significant difference was found in the two motor domains or the two language domains. A number of authors have suggested that these two domains may be particularly problematic for children with Down syndrome (Cunningham, 1987; Hanson, 1988; Share &c French, 1982). In the domain of motor development, the norms for children with Down syndrome have been reported in two key sources. Cunningham (1987) reported on the age at which developmental milestones were accomplished in children who were provided home intervention dur- ing their early years. For example, consider the following reported milestones: standing alone (18 months for children with Down syn- drome versus 11 months for normally developing children); walking alone (23 months versus 12 months); and walking down steps with help (36 months versus 17 months). Likewise, Share and French (1982) reported that some skills emerge considerably later in children with Down syndrome (walking upstairs with one hand held at 55 months versus 18 months), yet other skills were less delayed (jumping from a bottom stair at 54 months versus 36 months; riding a tricycle at 60 months versus 36 months). These delays suggest that children with Down syndrome are developing their motor skills at about one-half at FLORIDA INTERNATIONAL UNIV on June 17, 2015 tec.sagepub.com Downloaded from MODEL PRESCHOOL PROGRAM, 65 the rate of nonhandicapped children. Even though on both measures of gross motor development used in this study (CADS and BDI) the mean rates of development improved during the course of interven- tion, it may be that the length of time in the intervention was simply too short to have an impact on skills that are less responsive to instruc- tional change. These results are consistent with our previous report that gains in the gross and fine motor development of children with Down syndrome failed to reach an acceptable level of significance (Oelwein et al., 1985).

In the area of communication development of children with Down syndrome, significant gains were reported on the CADS but not on the BDI. In expressive language on the BDI, the mean rate of develop- ment during intervention actually decreased from the rate at pretest.

It has been reported frequently in the literature that children with Down syndrome have significant delays, as well as qualitative differences, in expressive communication (Sandall, 1988; Smith & Oiler, 1981; Stoel-Gammon, 1980). Perhaps this is attributable to the fact that non- verbal communication skills are assessed at earlier ages, and children with Down syndrome acquire and use these skills at ages and in ways that are more consistent with normally developing peers. As children age, tests require language skills that involve the acquisition and use of symbolic representations—skills that may develop more slowly in children with Down syndrome. The intervention program was effec- tive in teaching early language skills that had been derived from objec- tives taken from the CADS, but it was difficult for children with Down syndrome to demonstrate these skills on the BDI, particularly when test items required the use of symbols.

Another possible explanation for the differences in the area of communication deserves further consideration. The two tests differ on the total number of items in domains and age ranges. This is par- ticularly true in the communication sections, with the CADS includ- ing considerably more items than the BDI. The impact of this is that children have more opportunities to demonstrate possible gains. A fur- ther difference between the two tests relates to their purpose. The CADS is the basis for the curriculum; thus, test items are designed to serve as goals and objectives for instruction. This is not the case with the BDI. It is expected that students will demonstrate greater gains when a test-teach-test model serves as the basis for instruction. The finding that results on an independent measure (the BDI) support the results of the CADS strengthens the possibility that the instructional at FLORIDA INTERNATIONAL UNIV on June 17, 2015 tec.sagepub.com Downloaded from 66, TOPICS IN EARLY CHILDHOOD SPECIAL EDUCATION 11:1 model program has a positive effect on children with special learning needs. It is clear that further investigation is needed on this subsec- tion of the CADS.

There are other aspects of this study that convey information about the impact of intervention and about the role of measurement.

The results reported here are particularly encouraging, given the type of statistical analysis used. In this study we used a developmental rate to measure change. In a number of studies that have used this method, which is equivalent to achieving change in developmental quotient scores, studies have reported disappointing results (Bailey & Bricker, 1985; Holmes, Britain, Simpson, & Hassanein, 1987). In the Holmes et al. (1987) study, the intervention rates of children with Down syn- drome decreased dramatically, from a mean of 90 to a mean of 73 during the intervention period. Although the population of that group was younger than that reported in this study, Holmes et al. reported that chronological age accounted for only 3.2% of the variance when entered into the regression equation.

It is important to examine some of the characteristics of the MPP that might point to traits of effective programs. The model was well grounded in an approach to instruction that included the use of a devel-opmental curriculum, sequenced in all domains of development, that was taught through a test-then-teach model using systematic, individ-ualized instruction. Data were taken frequently, and pre- and post- test scores were shared with the model site. Parents were central to the implementation, and all staff were trained in the model and moni- tored in their adherence to the basic principles. Sites were allowed flex- ibility in the size of classes, age of students, and frequency, intensity, and duration of instruction. Whether states select this model or other models for implementation, they may want to be aware of these key elements in making decisions for future programs. The knowledge that this particular model has been tested in many sites and over several years using a number of dependent measures, and has repeatedly been found to be effective, adds support for its efficacy (Oelwein et al., 1985). Finally, a few points of caution need to be raised. First, this study is not a true experimental design, as there were no control or contrast groups or random assignment to groups. This kind of design would help answer questions as to whether this particular model program is more effective than a contrasting program. All that can be said is that the children's developmental rates during the program were sig- nificantly higher than when they entered the program. Second, the at FLORIDA INTERNATIONAL UNIV on June 17, 2015 tec.sagepub.com Downloaded from MODEL PRESCHOOL PROGRAM, 67 investigators were not able to separate completely the test examiners from those responsible for conducting the intervention. Both psychol- ogists and teachers participated in the administration of these tests.

Although data were reported directly to the study investigators, there were some instances in which teachers had knowledge of pretest results. While this is not a good practice in research, it is consistent with the instructional model advocated by this program. Specifically, teachers are encouraged to teach those skills in which the children fail to demon- strate competency. This was done on the CADS but not on the BDI.

Third, the length of this intervention and the actual time in instruc- tion can be factors that influence outcomes. This was not examined in the study, but should be examined in future research.

In conclusion, despite the weaknesses described, the study pro- vides additional support for the effectiveness of this instructional model. This study, with its population of 194 subjects, including a subgroup of 92 subjects with Down syndrome, is one of the largest multisite studies of children with special needs to receive a single, validated early intervention program. These results add support to the theoretical basis of P.L. 99-457 and the movement to invest more resources in the edu- cation of young children with handicaps and their families. References Bailey, E.J., & Bricker, D. (1985). Evaluation of a three-year early intervention demonstration project. Topics in Early Childhood Special Education, 5(2), 52-65. Cunningham, C. (1987). Down's syndrome: An introduction for parents. London: Souvenir Press.

Dunst, C, & Rheingrover, R. (1981). An analysis of the efficacy of infant interven- tion programs with organically handicapped children. Evaluation and Program Planning, 4, 287-323.

Fewell, R.R., & Oelwein, P.L. (1990). The relationship between time in integrated environments and developmental gains in young children with special needs. Topics in Early Childhood Special Education, 10(2), 104-116.

Hanson, M.J. (1988). Effects of gross-motor activities on development. In V. Dmitriev &c P.L. Oelwein (Eds.), Advances in Down syndrome (pp. 167-173). Seattle:

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Holmes, G.E., Britain, L.A., Simpson, R.L., & Hassanein, R.S. (1987). Develop- mental progress of five groups of disabled children attending an early interven- tion program. Physical and Occupational Therapy in the Pediatrics, 71(1), 3-18.

Mott, S.E., Fewell, R.R., Lewis, M., Meisels, S.J., Shonkoff, J.P., & Simeonsson, R.J. (1986). Methods for assessing child and family outcomes in early childhood special education programs. Topics in Early Childhood Special Education, 6(2), 1-15. at FLORIDA INTERNATIONAL UNIV on June 17, 2015 tec.sagepub.com Downloaded from 68, TOPICS IN EARLY CHILDHOOD SPECIAL EDUCATION 11:1 Newborg, J., Stock, J.R., Wnek, L., Guidubaldi, J., & Svinicki, J. (1984). Battelle developmental inventory. Allen, TX: DLM.

Odom, S., & Fewell, R.F. (1983). Program evaluation in early childhood special education: A meta-evaluation. Educational Evaluation and Policy Analysis, 6(4), 445-460.

Oelwein, P.L., Fewell, R.R., & Pruess, J.B. (1984). Developmental sequence per- formance inventory. Unpublished manuscript, University of Washington, Seattle.

Oelwein, P.L., Fewell, R.R., &c Pruess, J.B. (1985). The efficacy of intervention at outreach sites of the Program for Children with Down syndrome and Other Devel- opmental Delays. Topics in Early Childhood Special Education, 5(2), 78-87.

Oelwein, P.L., Fewell, R.R., & Pruess, J.B. (1988). Classroom assessment of devel- opmental skills. Unpublished manuscript, University of Washington, Seattle.

Sandall, S.R. (1988). Parent-child interaction: Learning to take turns. In V. Dmitriev &c P.L. Oelwein (Eds.), Advances in Down syndrome (pp. 261-269). Seattle:

Special Child Publications.

Share, J., & French, R. (Eds.). (1982). Motor development of Down syndrome chil- dren: Birth to six years. (Available from J.B. Share, 13546 Riverside Dr., Sherman Oaks, CA 91423) Smith, N.L. (1986). Evaluation alternatives for early intervention programs. In L. Bickman 8t D.L. Weatherford (Eds.), Evaluating early intervention programs for severely handicapped children and their families (pp. 185-207). Austin, TX: PRO-ED.

Smith, B.L., 8c Oiler, D.K. (1981). A comparative study of premeaningful vocaliza- tions produced by normally developing and Down syndrome infants. Journal of Speech and Hearing Disorders, 46, 46-51. Snyder-McLean, L. (1987). Reporting norm-referenced program evaluation data: Some considerations. Journal of the Division of Early Childhood, 11, 254-264.

Stoel-Gammon, C. (1980). Phonological analysis of four Down's syndrome children. Applied Psycholinguistics, 1, 31-48. at FLORIDA INTERNATIONAL UNIV on June 17, 2015 tec.sagepub.com Downloaded from