51 Early Communication Intervention with Young Children with Pierre Robin Sequence Lisl Fair and Brenda Louw Centre for Early Interv~ntion in Communication Pathology Department of Communication Pathology University of Pretoria ABSTRACT Young children with Pierre Robin sequence are at considerable risk to develop delayed or disordered communication development. This study investigated the effectiveness of early communication intervention with four young children wtth Pierre Robin sequence, aged 5 to 28 months. The Proportional Change Index (Wolery, 1983) was used to determine the amount of child progress that took place during the intervention period. The results indicated that regular early communication intervention sessions over an extended period of time produced positive results, especially for expressive language abilities. The presence of a slight hearing loss due to otitis media, seemed to have influenced the effectiveness of early communication intervention. One subject displayed an associated disorder and evidenced the slowest rate of development for receptive and expressive language abilities as well as a limited phonetic repertoire for consonants. All but one subject had limited phonetic repertoires possibly due to velopharyngeal incompetence. Early communication intervention services should be delivered regularly over an extended period of time and the hearing abilities and speech production skills of young children with Pierre Robin sequence should be followed closely during early communication intervention. OPSOMMING Jong kinders met Pierre Robin-volgpatroon vertoon risikofaktore om vertraagde of afwykende kommunikasie-ontwikkeling te he. Hierdie studie het die effektiwiteit van vroee-kommunikasie- intervensie met vier jong kinders met Pierre Robin- volgpatroon, tussen die ouderdomme van 5 en 28 maande, ondersoek. Die Proporsionele Veranderings-indeks (Wolery, 1983) is aangewend om die mate waarin die proefpersone tydens die intervensie-tydperk gevorder het, aan te dui. Die resultate het aangetoon dat gereelde vroee-kommunikasieLintervensie sessies oor 'n uitgebreide tydperk, veral vir ekspressiewe taalvaardighede, positiewe resultate lewer. Die teenwoordigheid van 'n geringe gehoorverlies as gevolg van otitis media, het moontlik die effektiwiteit van vroee-kommunikasie-interven'sie bei"nvloed. Een proefpersoon het Pierre Robin-volgpatroon en 'n geassosieerde afwyking getoon en die resultate het aangetoorl dat haar ontwikkelingstempo vir reseptiewe en ekspressiewe taalvermoens die stadigste was en ook dat sy 'n beperkte foneti~se repertoire vir konsonante getoon het. Drie uit die vier proefpersone het beperkte fonetiese repertoires getoon, moontlik bs gevolg van velofaringeale onbevoegdheid. Vroee-kommunikasie-intervensie-dienste aanjong kinders met Pierre Robin-vblgpatroon behoort op 'n gereelde basis oor 'n uitgebreide tydperk gelewer te word en die gehoorvermoens en spraakproduksie-vermoens van hierdie kinders moet gemonitor word gedurende intervensie. I KEY WORDS: Pierre Robin;sequence, early communication intervention, effectiveness In the past two decades young children with commu- nication disorders have received increased attention within the field of Communication Pathology (Guralnick, 1997). Any factor illfluencing the way a child interacts with his environment can be considered to be a potential risk factor contributing to a developmental delay (Rossetti, 1996). Infants with Pierre Robin sequence are classified as high- risk infants since a number of risk factors are associated with Pierre Robin sequence (Elliot, Studen-Pavlovich & Ranalli, 1995). Three distinct symptoms mark the presence of Pierre Robin sequence in a young child, namely mandibular hypoplasia, glossoptosis as well as a wide U-shaped cleft of the palate (Shprintzen & Bardach, 1995), which cause a number of medical problems1for these children. Elliot et al. (1995) list the following medical complications frequently occurring in young children with Pierre Robin sequence: airway obstruction, hypoxia, respiratory infections, otitis media and feeding problems like an insufficient sucking pattern and aspiration. In addition to these medical complications, children with Pierre Robin sequence may also exhibit problems like cerebral palsy (Bull, Givan, Sadove, Bixler & Hearn, 1990), congenital heart problems, cognitive impairments and visual problems (Sadewitz, 1992). The medical care necessitated by these early medical complications and associated disorders often require that infants with Pierre Robin sequence are hospitalized for prolonged periods of time (Savage, 1997). The communication development of young children with Pierre Robin sequence is traditionally described as being characterised by the same impairments as that of children with cleft lip and palate, namely: velopharyngeal incom- Die Suid-Afrikaanse Tydskrif vir Kommunikasieafwykings, Vol. 45, 1998 R ep ro du ce d b y Sa bi ne t G at ew ay u nd er li ce nc e gr an te d by th e P ub lis he r ( da te d 20 12 ) 52 petence, nasal emission, hypernasality, compensatory articulation patterns and delayed language development (McWilliams, Morris & Shelton, 1990). Infants with cleft lip and palate are classified as presenting an established risk for communication disorders (Rossetti, 1996), but the combination and magnitude of the risk factors present in the case history of most young children with Pierre Robin sequence can have an even greater influence on their communication development. A combination of established, biological and environmental risk factors are often associated with young children with Pierre Robin sequence and may have a negative influence on the way a child with Pierre Robin sequence interacts with his environment. These risk factors are summarised in Table 1. Children with Pierre Robin sequence are described in- depth in the literature due to the complexity ofthe disorder (Sadewitz, 1992) and special attention is given to research on the early medical complications accompanying Pierre Robin sequence (Bull et aI., 1990; Elliott et aI., 1995; Sadewitz, 1990). In spite of the number of studies on the medical complications of Pierre Robin sequence and the at- risk status of young children with Pierre Robin sequence, a dearth in the literature exists regarding information about the outcome of their communication development. An early study conducted by Pashayan and Lewis in 1984 provided information regarding the speech- and language develop- ment of children with isolated Pierre Robin sequence as well as of children with Pierre Robin sequence and an additional syndrome. The speech- and language develop- ment of children with isolated Pierre Robin sequence was found to be impaired and the speech-and language development ofthose children with Pierre Robin sequence and an additional syndrome was found to be even more impaired and delayed than those with isolated Pierre Robin sequence. Since the study conducted by Pashayan & Lewis (1984), limited research was reported on the communication development of young children with Pierre Robin sequence, rendering their work to be a valuable source of information on the early communication development of these children. According to Shprintzen and Bardach (1995) additional syndromes exist in more than half of all Pierre Robin sequence cases, such as Stickler syndrome (34% of all Pierre Robin sequence cases) and Velocardial Facial syndrome (11% of all Pierre Robin sequence cases). The presence of an additional syndrome in young children with Pierre Robin sequence places them at greater risk to display delayed or disordered communication development. Speech-language therapists delivering services to young children are advised to take cognisance ofthe fact that a relatively high number of children with Pierre Robin sequence may have an additional syndrome and to provide services that are responsive to the individual needs of each child (Shprintzen & Bardach, 1995). LislFair & Brenda Louw The presence of a hearing impairment can also negatively influence the communication development of young children with Pierre Robin sequence. Handzic, Bagatin, Subotic and Cuk (1995) found that these children are at-risk for a congenital sensory-neural, conductive or mixed hearing loss, with or without the presence of congenital malformations of the ear. These authors also found that children with Pierre Robin sequence have a slight hearing loss due to middle ear effusions. Elliot et al. (1995) further indicate that 90,9 % of all children with Pierre Robin sequence have at least one episode of otitis media. The presence of a slight hearing loss may have a negative influence on the communication development of a child since receptive language development is dependent on adequate and constant auditory input (Friel-Patti, 1990). Due to the established risk displayed by young children with Pierre Robin sequence, early communication intervention seems to be the only viable option in considering treatment alternatives. Early communication intervention is a relatively new field of study within the discipline of Communication Pathology and is currently viewed as the best form of intervention for at-risk children (Rossetti, 1996). Early communication intervention is aimed at the prevention of communication disorders by facilitating communication development and optimising developmental outcome through parent centred therapy (Savage, 1997; Kritzinger, Louw & Hugo, 1996). The revision of the South Mrican Speech-Language Hearing Association's Code of Ethics in 1997, placed renewed focus on the issue of accountable and effective service delivery in South Africa (SASHLA, 1997). The revised Code of Ethics emphasises the fact that clients should benefit from service delivery and that professionals should adhere to their professional responsibility in conducting speech-language therapy services (SASHLA, 1997). According to Carney (1996) and Boston (1994) accountable and effective service delivery is important since data from effective service delivery can be used in advocacy activities like motivating the allocation of funds from medical aid schemes and donor organisations. The early communication intervention services rendered by speech- language therapists to young children with Pierre Robin sequence should be accountable and effective to en'sure that these children gain maximum benefit from intervention and reach their full developmental potential. I The provision of early communication intervention services to at-risk children is strongly advocated: and the effectiveness ofthese practices is a current topic in literature (Lee & Khan, 1997). Several authors concur that early communication intervention programmes ar~ indeed effective, but factors influencing the effectiveness of these programmes have been identified (Rossetti, 1996; Savage, TABLE 1: Risk factors associated with Pierre Robin sequence(compiled from Rossetti, 1996; Sadewitz, 1992 and Savage, 1997). ' Established Environmental Biological /' risk factors risk factors risk factors / , , • Pierre Robin sequence • Prolonged and multiple • Respiratory problems - • Associatied disorders hospi talization • Feeding problems • Disruption of parent-infant • Failure to thrive interaction • Recurrent otitis media • Family stressors The South African Journal of Communication Disorders, Vol. 45, 1998 R ep ro du ce d b y Sa bi ne t G at ew ay u nd er li ce nc e gr an te d by th e P ub lis he r ( da te d 20 12 ) Early Communication Intervention with Young Children with Pierre Robin Sequence 53 1997; Guralnick, 1997). Factors influencing the effectiveness of earlY intervention include: the age of onset ofintervention (the younger, the more benefit), degree of involvement of the parents (the more involved the greater the benefit), home and centre based components included in the programme (both should ideally be included) and the quality of intervention services (the higher the quality the higher the benefits) (Rossetti, 1996; Savage, 1997; Guralnick, 1997). Speech-language therapists delivering early communication intervention services to young children with Pierre Robin sequence should take cognisance of these factors and incorporate them into service delivery to ensure that a high standard of service delivery is maintained. The measurement of effective service delivery in early communication intervention is currently a controversial subject in literature (Lee & Khan, 1997), since the amount of child progress has traditionally been used to determine the effect of early intervention. By simply comparing pre- and post intervention data to determine child progress, the effect of natural maturation is not accounted for and the comparison may yield a false picture of the effect of intervention on the development of the child (Rossetti, 1996). Lee and Khan (1997) suggest that the natural maturation of the child as well as the child's rate of development prior to intervention should be taken into consideration when determining child progress and programme effectiveness. Any formula used to determine child progress and programme effectiveness must account for these two factors, to ensure that the progress in development is due to intervention and not only to natural maturation (Lee & Khan, 1997). Currently several methods of measuring the develop- mental progress of children in early communication intervention programmes, exist. These include develop- mental age comparisons, developmental quotient compa- risons, indexes of change, actual- predicted score comparisons and modelling individual growth (Lee & Khan, 1997). In a study conducted to determine the most effective way to determine child progjess and programme effec- tiveness Lee & Khan (1997) applied all ofthese methods to a sample of children who recei{red early intervention. Their results indicated that using hn index of change, namely the Proportional Change Inde*- (PC!), which was developed by Wolery (1983), provides the most appropriate way of measuring child progress and~ programme effectiveness in early intervention. By meas~ring change in the rate of development, this method acc6unts for natural maturation as well as the child's rat~ of ,development prior to intervention and will therefore provide an accurate indication of the progress a child has made in intervention. The early communication intervention approach currently used in the Centre for Early Intervention in Communication Pathology, Department of Communication Pathology, University of Pretoria is a parent centred approach and was developed as an appropriate and effective approach to early communication intervention by Louw & Hugo (1987). It includes the use of three intervention strategies namely education, counselling and training of parents, and intervention sessions are conducted monthly due to the distances parents often have to travel as well as the limited number of speech-language therapists providing early intervention services in South Mrica (Louw & Hugo, 1987; Louw, Hugo, Kritzinger & Pottas, 1997). Speech-language therapist~ in SouthMrica applying this approach and aiming to provide quality services to the young children with Pierre Robin sequence need to be aware of matters pertaining to the measurement of effectiveness in early communication intervention. Rossetti (1996) stresses the importance of accountable service delivery in early communication intervention by referring to the term best practice. He concludes that best practice can only be achieved by carefully measuring programme outcomes. In order to establish whether the early communication intervention approach currently being used in South Africa for the treatment of young children with Pierre Robin sequence constitutes best practice it is necessary to measure the outcome of intervention. The measurement of the effectiveness of early communication interventiori with young children with Pierre Robin sequence may provide an indication of the appropriateness and possible shortcomings in the approach currently followed. The aim of this study is to establish whether early communication intervention with young children with Pierre Robin sequence is effective. METHODOLOGY 1. AlMS The purpose of this study was to determine the effectiveness of early communication intervention with four young children with Pierre Robin sequence and the following sub- aims were formulated: • the measurement of the effectiveness of early commu- nication intervention for the receptive language abilities of the subjects, • the measurement of the effectiveness of early commu- nication intervention for the expressive language abilities of the subjects, • the measurement of the effectiveness of early commu- nication intervention for the cognitive abilities of the subjects and, • the measurement of the effectiveness of early commu- nication intervention for the speech production abilities of the subjects. 2. RESEARCH DESIGN An ABA quasi-experimental case study research design was used to measure the progress of the subjects in intervention because all the variables in the study could not be controlled (McBurney, 1994). The phases of the research process are graphically depicted in Figure 1 and included the following: the AI phase consisted of the pre-treatment assessment conducted in the Clinic for High Risk Infants (CHRIB) at the Centre for Early Intervention in Communication Pathology, Department of Communication Pathology, University of Pretoria. The B phase consisted of early communication intervention, which the subjects received for varying periods of time and the ~ phase consisted of the post-treatment assessment conducted in the home of each subject. This research design allows for the description of the individual performance of each subject but the design does not allow for generalisation ofthe findings (McBurney, 1994). 3. SUBJECTS The subjects (Ss) were extracted retrospectively from file data at the Clinic for High Risk Babies (CHRIB), which Die Suid-Afrikaanse Tydskrifvir Kommunikasieafwykings, Vol. 45, 1998 R ep ro du ce d b y Sa bi ne t G at ew ay u nd er li ce nc e gr an te d by th e P ub lis he r ( da te d 20 12 ) 54 PhaseA. Pre-treatment assessment conducted at CHRIB PhaseB Early communication intervention Phase~ Post-treatment assessment conducted at the home of each subject FIGURE 1: Phases in the research process serves as a diagnostic and intervention facility for the Centre for Early Intervention in Communication Pathology, aimed at service delivery to high risk infants and toddlers and their families. A total of four subjects were available when the following criteria were applied: the subjects must have been diagnosed as having Pierre Robin sequence and they must have been between 5 and 30 months of age during the post-treatment assessment. The following factors were not considered during the selection procedure: number of early communication intervention sessions received, the presence of associated disorders and slight to moderate prematurity. The absence of associated disorders were not included in the selection criteria since Shprintzen and Bardach (1995) found that more than fifty percent of children with Pierre Robin sequence also display associated disorders. Slight to moderate prematurity was also not considered since Caouette-Laberge, Bayet and Larocque (1994) indicated that up to eight percent of infants with Pierre Robin sequence are born prematurely. The four subjects' ages ranged from 5 months to 28 months and all received early communication intervention for varying periods, initiated after each subject's pre- treatment assessment. One subject (S4) displayed an associated disorder (Velocardial-facial syndrome) as well as slight prematurity and another (SI) evidenced moderate prematurity. All of the subjects had had episodes of otitis TABLE 2: Description of the subjects (n=4) Characteristics Subject 1 Gender Male Pre-treatment age in months 11 , Post-treatment age in months 25 Diagnosis Pierre Robin sequence Prematurity Moderate Associated disorders None Medical problems Otitis media ECI received (months) 14 ECI received (sessions) 13 ECI received at Private Practitioner Key: ECI = Early Communication Intervention Lisl Fair & Brenda Louw media. Table 2 provides a detailed description of the subjects. 4 PROCEDURE 4.1 ASSESSMENT AND DATA COLLECTION Each subject underwent comprehensive pre- and post- treatment assessments utilising the CHRIB Evaluation Protocol (Louw & Kritzinger, 1994). The CHRIB Evaluation Protocol (Louw & Kritzinger, 1994) covers all aspects of early communication development and includes the use of several other published evaluation instruments, as well as clinical guidelines for the interpretation of descriptive data. The pre-treatment assessments of all four subjects were conducted in CHRIB by the same experienced clinicians, whereas the post-treatment assessments were carried out in the homes of the subjects by the first author. The post- treatment assessments were conducted in the homes of the subjects as the home environment is considered to be a naturalistic context and a more reliable representation of the child's functioning can be obtained in the context of the child's home (Rossetti, 1996). The fact that the pre- and post-treatment assessments were not conducted in the same setting implies that an extra variable was introduced, but as the data used in this study was part of a wider research project (Fair, 1997) this variable could not be controlled. During both the pre- and post-treatment assessments an interview was conducted with the parents of the subjects in order to obtain background information and the subjects' communication- and general developmental skills were elicited in a controlled play context. Infant behaviour was recorded using evaluation instruments such as the Rossetti Infant Toddler Language Scale (Rossetti, 1990), the Developmental Assessment Schema (DAS) (Anderson, Nelson & Fowler, 1978), as well as the Developmental Activities Screening Inventory II (DASI-II) (Fewell & Langley, 1984). Infant behaviours such as vocalizations and verbalizations were also recorded and used as descriptive data. Video- and audio-recordings were made during both the pre- and post-treatment assessments utilizing a Subject 2 Subject 3 Subje~t 4 I , Female Female Fem~le , , 9 10 5' 28 19 10 Pierre Robin Pierre Robin Pierre Robin sequence sequence sequence None - None Slight None None Velocardial- Facial syndrome Otitis media Otitis media .. Otitis media 19' 9 5 14 1 2 CHRIB CHRIB CHRIB The South African Journal of Communication Disorders, Vol. 45, 1998 R ep ro du ce d b y Sa bi ne t G at ew ay u nd er li ce nc e gr an te d by th e P ub lis he r ( da te d 20 12 ) Early Communication Intervention with Young Children with Pierre Robin Sequence 55 Panasonic R33 VHS-C Movie Camera and a Sakyno SK-2100 Portable Cassette Recorder. These recordings were used to accurately document and describe infant behaviours. After the data was collected it was processed by using guidelines and procedures described in the published materials and literature in order to determine the developmental levels of the subjects and to describe their behaviour accurately (Rossetti, 1990; Anderson et al., 1978; Fewell & Langley, 1984; McWilliams et al., 1990; Shprintzen & Bardach, 1995). For the purpose of this study only evaluation areas pertaining to communication development were considered since the main focus of early communication intervention is the facilitation of communication skills (Louw & Kritzinger, 1991). These areas were receptive and expressive language development, cognitive development and the speech production abilities of the subjects. Cognitive development was included in the study as Rossetti (1996) indicated that in children younger than twenty four months of age the development of language and cognition is so integrated that it cannot be separated and Louw & Kritzinger (1991) list the facilitation of cognitive development as an aim for early communication intervention. A data collection form was compiled and the following information was copied from the pre-and post-treatment evaluation data in order to analyse the data: the develop- mental ages of the subjects yielded by the Rossetti Infant Thddler Language Scale (Rossetti, 1990) for receptive and expressive language abilities, the developmental age of the subjects for cognitive development, determined by the DASI- II (Fewell & Langley, 1984) and a qualitative description of the subjects' phonetic repertoires for consonants. Although the CHRIB Evaluation Protocol (Louw & Kritzinger, 1994) allows for eliciting and describing information regarding the type and number of consonants, syllable structure as well as the level of vocalizations during the evaluation of speech production abilities, only the type and number of consonants were considered in this study. The type and number of consonants were selected and qualitatively described as ,children with Pierre Robin sequence often display limited phonetic repertoires and experience problems in prodricing pressure consonants and fricatives (McWilliams et al.! 1990, Shprintzen & Bardach, 1995). I 4.2 DATA ANALYSIS I I The data regarding the receptive, expressive and cognitive development ofthe subjects on the data collection form was analysed and compared using the Proportional Change Index (PCI) (Wolery, 1983) to determine the amount of child progress that took place. The PCI is calculated using the following formula: PCI (Developmental gain in months + Time in intervention in months) + (Pretest developmental age + Pretest chronological age). Mter calculation the PCI (Wolery, 1983) yields a numerical statement of the relationship between the rate of development prior to intervention and the rate of development during intervention. A score of 1.0 indicates that the rate of development prior to intervention is identical to the rate of development during intervention, while a score of more thdn 1.0 shows that the rate of development during intervention is faster than the rate of development prior to intervention. A score ofless than 1.0 indicates that the rate of development during intervention is slower than the rate of development prior to intervention. If the PCI score surpasses 1.0 the programme is regarded as effective (Lee & Khan, 1997; Wolery, 1983). The data on the data collection form regarding the phonetic repertoires of the subjects was analysed by comparing the number of consonants that the subjects used during the pre- and post-treatment assessments, as well as listing the different consonants that the subjects used during the pre-and"post-treatment assessments. As clinical guidelines for assessing the development of consonants are not readily available and a developmental age level pertaining to this area of communication development could therefore not be established, the PCI (Wolery, 1983) was not used in the analyses of the phonetic repertoires of the subjects. Oller, Eilers, Steffens, Lynch and Urbano (1994) describe alternative approa~hes to measuring the development of consonants in young children but as the data used in this study was part of a wider research project (Fair, 1997), the CHRIB Evaluation Protocol (Louw & Kritzinger, 1994) was deemed to be appropriate to assess this area of development. The results of the receptive, expressive and cognitive developmental progress of the subjects as well as the qualitative description of the phonetic repertoires of the subjects were then further analysed by using descriptive statistics in order to display the results graphically in the form of bar charts. RESULTS AND DISCUSSION The developmental age levels of the subjects pertaining to their receptive and expressive language development, as well as cognitive development, is presented in Figure 2 in order to provide an overview of the development of the subjects during the pre- and post-treatment assessments. Figure 3 indicates the chronological ages of the subjects at the time of the pre- and post-treatment assessments. All the subjects showed progress in receptive and expressive language development as well as cognitive development from the pre-treatment assessment to the post- treatment assessment, as indicated in Figure 2. During the post-treatment assessment subject one and four evidenced delayed development in receptive and expressive language development as well as in cognitive abilities (See Figures 2 and 3). Subject two's developmental age for receptive- and expressive language development as well as cognitive abilities during the post-treatment assessment was slightly above her chronological age whereas subject three evidenced appropriate development for cognitive abilities and receptive language abilities but showed a delay in her expressive language development during the post- treatment assessment (See Figures 2 and 3) RECEPTIVE LANGUAGE ABILITIES Figure 4 indicates that two of the four subjects (Ss1 and 2) showed faster rates of development during intervention than prior to intervention, as their PCI scores were 1.14 and 1.42 respectively. Subjects three and four showed slower receptive language development during intervention than prior to intervention, their scores being 0.91 and 0.8 respectively. Die Suid-Afrikaanse TydskrifuirKommunikasieafwykings, Vol. 45, 1998 R ep ro du ce d b y Sa bi ne t G at ew ay u nd er li ce nc e gr an te d by th e P ub lis he r ( da te d 20 12 ) 56 The fact that subjects one and two's rate of development was accelerated during intervention may be attributed to the number of early communication intervention sessions they attended, which amounted to thirteen and fourteen respectively (See Table 2). Subjects three and four only attended one and two early communication intervention sessions respectively and were also involved in intervention for a shorter period of time (See Table 2). These results seem to indicate that greater benefit is derived from early communication intervention if sessions are presented at least once a month over an extended period of time. This finding is in agreement with the early communication intervention approach used at CHRIB (Louw and Kritzinger, 1991) during which early communication intervention is conducted monthly from when the child enters the programme until approximately twenty four months of age after which intervention becomes more child centered and is provided on a twice monthly or weekly basis. All the subjects displayed episodes of otitis media during 33 '" 30 -B 27 c 0 S 24 .8 Il.) 21 gl 18 til 15 .... Q Il.) 12 §, 0 9 ~ 6 Il.) 0 3 0 2 Key: Lisl Fair & Brenda Louw the intervention period and the slight hearing loss associated with otitis media could have had a negative influence on the rate of their receptive language development (Friel-Patti, 1990). Subject four, who obtained the lowest score had chronic otitis media with effusion during the whole intervention period and the severity of the condition could have influenced her rate of development during the intervention period in particular. In addition to the otitis media, her rate of development for receptive language could also have been influenced by the Velocardial-facial syndrome she displays, since Shprintzen and Bardach (1995) indicated that children with Velocardial-facial syndrome exhibit delayed language development, as well as by the fact that she had only attended two therapy sessions. EXPRESSIVE LANGUAGE ABILITIES Figure 5 illustrates the rate of development of the subjects' expressive language abilities. Their PCI scores 3 4 Subjects EI Receptive language skills at pre-treatrrent assesstrent fJll Receptive language skills at post-treattrent assesstrent \ IIID Bq:>ressive language skills at pre-treatrrent assesstrent rEI BqJressive language skills at post-treat:rrent asses~rrent m Cognitive abilities at pre-treatrrent assesstrent FIGURE 2: Developmental ages of the subjects .5