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44 Journal of Intellectual Disability Research doi: 10.1111/j.1365-2788.2008.01121.x

volume 53 part 1 pp 44–53 january 2 9

Reliability and validity of the revised Triple C: Checklist of Communicative Competencies for adults with severe and multiple disabilities

T. Iacono,1 D. West,2 K. Bloomberg2 & H. Johnson2

1 Centre for Developmental Disability Health Victoria, Monash University, Melbourne,Victoria, Australia and the Communication Resource Centre, Scope, Melbourne,Victoria, Australia 2 Communication Resource Centre, Scope, Melbourne,Victoria, Australia

Abstract

Aims Few tools are available to assess the commu- nication skills of adults with severe and multiple disabilities functioning at unintentional to early symbolic levels. An exception is the Triple C: Checklist of Communicative Competencies. In this study, aspects of support worker and clinician agreement, internal consistency and construct valid- ity of a revised version of the Triple C were explored. Method Triple C checklists were completed for 72 adults with severe intellectual disabilities (ID) by 118 support workers and stages were assigned by the researchers. Two support workers completed checklists for each of 68 adults with ID. Three researchers also conducted direct observations of 2 adults with ID. Results The average support worker agreement for items across the five stages of the Triple C ranged from 81% to 87%; agreement for stage assignment based on first and second support worker checklists was moderate to high (k = .63). Internal consis- tency was high (KR2 = .97); the stages were found to tap one factor (accounting for ~74% of variance), interpreted to be unintentional to early

Correspondence: Associate Professor Teresa Iacono, Centre for Developmental Disability Health Victoria, Monash University, Building 1, 27 Ferntree Gully Road, Nottinghill, Victoria, Austra- lia, 3166 (e-mail: [email protected]).

symbolic communication. Agreements between stages based on researcher observations and support worker-completed checklists were 35% and 71% across first and second support workers. Conclusion The revised Triple C provides a reliable means of gathering data on which to determine the communication skills of adults with severe and mul- tiple disabilities. The results support a collaborative use of the Triple C, such that a speech-language pathologist or other communication specialist works with a support worker to ensure understanding of the skills observed and development of appropriate intervention strategies.

Keywords communication, assessment, intellectual disability, proxy reports, direct carers

Introduction

For adults with developmental disabilities, access to specialist services, such as speech pathology, can be limited (Stancliffe 2 6). In Australia (Bloomberg et al. 2 3) and the UK (Money 2 2), for example, such limited access seems to be the impetus for training support workers (i.e. paid care staff) in small group residences or day services to implement communication interventions with their clients with developmental disabilities. A conse- quence has been reliance on these support workers

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T. Iacono et al. • Triple C reliability and validity

to provide data needed for communication assess- ment, which, in turn, can inform service-based interventions.

The extent to which paid care staff can be relied on to provide accurate information has been of some concern. Purcell et al. (1999), for example, found that paid residential and day-placement staff tended to overestimate the language-comprehension abilities of their clients. They also had difficulty with identifying their non-verbal signals. The ability of staff to judge their clients’ abilities has relevance to the use of assessments that rely on proxy reports. Such reporting is used for assessment in a number of areas, such as health (Iacono & Sutherland 2 6; Wang et al. 2 7), psychopathology (Moss et al. 1998), challenging behaviour (Newton & Sturmey 1991; Harris et al. 1994), quality of life (Campo et al. 1997; Stancliffe 1999) and communication (van der Gaag 1989; Purcell et al. 1999; Iacono et al. 2 5).

Investigations into the reliability of proxy report- ing by paid care staff have varied in both method and outcomes. Stancliffe (1999), for example, reported a correlation of .59 between scores on the Quality of Life Questionnaire Empowerment factor (measuring choice and control) based on self- reports by adults with intellectual disabilities (ID) and those of their paid carers. The correlation between two paid carers rating the same adult with ID was .73. Harris et al. (1994) compared ratings on two scales of the Checklist of Challenging Behaviour (Aggression and Other Challenging Behaviours) by conducting two interviews with two paid carers for each adult with ID. Agreement between the two checklists ranged from 75% to 77% across the scales for frequency, severity and management difficulty. Moss et al. (1998) provided reliability data on individual items of the Psycho- logical Assessment Schedule for Adults with Devel- opmental Disabilities (PAS-ADD) Checklist on the basis of data provided by key informants, including paid carers. Cohen’s kappa scores for individual item agreement ranged from as low as .3 to .7, but the overall kappa was .79. The authors argued, however, that the reliability measure of most concern was that which determined the extent to which raters’ scores agreed as to whether the indi- vidual was above or below the thresholds for pos- sible psychological disturbance, which would trigger

a referral for a complete psychiatric assessment. They reported 79% agreement between raters on whether or not at least one threshold for the three sub-scales had been crossed.

In terms of judgements about communication behaviours, Iacono et al. (1998) reported difficulties in obtaining agreement for judgements about the intentionality and functions of communication of children with severe and multiple disabilities. Carter & Iacono (2 2) found that professionals, including speech pathologists and special education teachers, demonstrated inconsistencies in their judgements about the intentional communication of children with severe and multiple disabilities, children with Down syndrome, and even a child without disabil- ity. These difficulties, however, may result from asking observers to make overall judgements, as opposed to reporting behaviours seen, for example, asking if a person has been observed to search for an object that has disappeared from view as opposed to having demonstrated pre-intentional or intentional communication.

An additional complication may be the extent to which the person being asked to rate or make judgements about an individual’s communication regularly interacts with that individual. Granlund & Olsson (1993) compared observational versus teacher interview data on communication behav- iours of adults and adolescents with profound ID. The communication behaviours were analysed for communication complexity (i.e. developmental level of the form used, such as pointing and looking vs. pointing only) and frequency. They obtained higher correlations when comparing interview data obtained from the same teacher who interacted in videos (used to code observational data) across the functions of social interaction, joint attention and behavioural regulation (r = .6 , .83, .6 respectively) than when a different teacher parti- cipated in the two conditions (r = .5 , .32, .3 respectively).

van der Gaag (1989) argued that direct care staff of adults with ID have a wealth of knowledge and experience about the individuals in their care. On a premise of equal status between professionals and carers, she developed the Communication Assess- ment Profile (CASP). In the first part of the CASP a carer reports on the communication functions displayed by an individual with ID, and the every-

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T. Iacono et al. • Triple C reliability and validity

day situations in which that individual participates. The second part of the CASP is completed by a speech pathologist, based on observation of the individual. The third part, which is jointly com- pleted by the speech pathologist and carer, is used for intervention planning. van der Gaag reported on the reliability of carer ratings by comparing those of a person with ID’s key support worker with those of a support worker who had regular contact with, but no particular responsibility for that person. An overall correlation between these support worker ratings was .72; agreements between support worker ratings and speech pathologists’ observations (Parts 1 and 2 of the CASP) ranged from 5 % to 85%, while agreement between speech pathologists ranged from 81% to 99%.

Purcell et al. (1999) further explored the reliabil- ity of paid direct staff reports on the CASP by com- paring their ratings of adults with ID with assessments conducted by speech pathologists. In addition, the support workers rated the adults’ non- verbal signals before and after a 15-min interaction session, and the communication behaviours of both the support workers and their clients during a natural interaction were analysed by the researchers. Support workers volunteered for the study and selected a client with whom they were comfortable and felt they knew well. Agreement between their ratings of non-verbal behaviours from before versus after the interaction session ranged from 53% to 71% for non-verbal communication and from 42% to 79% for communicative functions. Agreements between support worker and speech pathologists’ ratings ranged from as low as 37% to 95% for non- verbal behaviours and from 58% to 92% for com- municative functions. Comparisons of support worker ratings and researcher counts based on observations indicated that the support workers had particular difficulty in rating non-verbal signals and the function of commenting.

Despite the poor results for both intra- and inter- rater reliability for direct care staff data, arguments have been made for including support workers as key players in the communication assessment and intervention of their clients (e.g. van der Gaag 1989; Bloomberg et al. 2 3). According to van der Gaag (1989), support workers can provide informa- tion about their client’s communication behaviours and skills that are not readily available to a profes-

sional. In particular, professionals have limited opportunities for interaction and observation of a client; in contrast, support workers experience prolonged engagement with clients across daily activities.

Further argument for involving support workers comes from a movement towards providing tertiary level communication interventions with a focus on enhancing functional outcomes within everyday situations (Granlund et al. 1995). Such approaches must involve those who interact with people with disabilities on a daily basis, in particular, family and/or direct paid staff. The variable data on the reliability of communication information obtained from paid carers suggest a need for providing them with sufficient information to enable them to understand and recognise the behaviours being assessed (Purcell et al. 1999). In addition, Iacono et al. (2 5) suggested that the process of partici- pating in an assessment process in collaboration with a professional could, in itself, act to increase the carer’s knowledge of and sensitivity to poten- tially communicative behaviours. Difficulty with rec- ognising communication appears to be of particular concern for adults with severe communication impairment who do not demonstrate spoken or even symbolic skills. For these individuals, both observation and recognition of non-verbal behav- iours as possibly communicative are needed to obtain comprehensive information about their com- munication skills and potential (Iacono et al. 1998; Purcell et al. 1999; Carter & Iacono 2 2).

Unfortunately, there are few assessment protocols developed specifically for adults with ID, particu- larly those that tap unintentional or intentional but non-symbolic communication behaviours (Iacono & Caithness in press), which characterise many indi- viduals at severe to profound levels of ID (McLean et al. 1999). An exception is the Triple C: Checklist of Communicative Competencies, designed by Bloomberg & West (1999) to determine the com- munication skills of adolescents and adults with severe and/or multiple disabilities. The target group are individuals who are unintentional or early intentional/symbolic communicators; hence they are functioning well below the level at which other communication assessments begin (e.g. Dewart & Summers, undated). The Triple C is administered by support workers and others who are familiar

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T. Iacono et al. • Triple C reliability and validity

with the individual. A retrospective study of 172 completed Triple C checklists by Iacono et al. (2 5) demonstrated the tool’s internal consistency and its underlying single factor structure. However, a problem was evident with Stage 1, which was found to have internal consistency that although adequate (KR2 = .77), was lower than those obtained for the other five stages (KR2 of .85 or above). On the basis of these results, the Triple C was revised by: (1) collapsing the original Stages 1 and 2 items (with some deletions); (2) requiring a response for all items on the checklist by checking boxes to indicate observed or not observed (as opposed to providing a check mark only if observed); and (3) changing some terminology and examples on the basis of feedback from support workers and clinicians. The inter-rater reliability of the Triple C was not determined in that first study, and with the changes made, there was also a need to address the construct validity and internal con- sistency of the revised tool.

Aim

The aim of the current study was to determine support worker agreement, internal consistency and underlying constructs for the revised version of the Triple C, and the extent to which data obtained from the tool compared with direct observations by clinicians.

Method

Ethics

Approval for the conduct of the study was obtained from two formally constituted Human Research Ethics Committees and a disability organisation’s ethics committee. Proxy consent from the next of kin or guardians of adults with ID was obtained given that the criteria for inclusion precluded their ability to provide their own consent. Direct consent was obtained for support worker participation.

Participants

Adults with intellectual disability

The criteria for inclusion of adults with ID were that: (1) they were not linguistic (i.e. vocabulary

was less than 5 words, and any word combinations were rote productions); and (2) consent had been received for information about them to be included in the study. Seventy-two adults with ID (44 men, 28 women) participated, aged from 2 to 7 years (mean = 41, mode = 36). All had ID (nine had Down syndrome). Additional reported disabilities were Autism Spectrum Disorder (n = 14) and cerebral palsy (n = 18). Ten participants had reported uncorrected vision impairment, four had reported hearing impairment, and 21 were non-ambulatory. Twenty of the adults (15 men, 5 women) also participated in direct observations. They were aged 2 –7 years (mean = 37 years): one had Down syndrome, and in addition to other forms of ID, five were reported to have Autism Spectrum Disorder and four to have cerebral palsy.

Support workers

The criteria for the inclusion of support workers were that they (1) had not had training or experi- ence in using the Triple C; and (2) had worked for at least 6 months with an adult with ID for whom consent had been received. The support workers came from accommodation and day services for adolescents and adults with severe and/or multiple disabilities in both rural and metropolitan regions across Victoria, Australia. A total of 118 support workers consented to participate in the study (89 women, 29 men). They had been support workers for a mean of 9 years (range from �1 year to 33 years) and had worked with their target adult with ID for a mean of 4 years (range = less than a year to 15 years). The highest level of education was Year 9, 1 or 11 of high school for 33 support workers, high school (i.e.Year 12) for 26, Tertiary and Further Education for 37, and University for 12 (1 participants did not provide this information).

Most support workers (n = 76) completed check- lists for only one target adult with ID, but 25 com- pleted them for two adults, five for three adults and two for four adults.

Revised Triple C checklist

The revised checklist comprises five stages that reflect the continuum from unintentional

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T. Iacono et al. • Triple C reliability and validity

to symbolic communication. These stages are described, with sample items provided in the Appendix.

Procedures

Each support worker attended a 2–3-h training session on how to complete a Triple C checklist, conducted by one of the researchers. In the train- ing, videos and case examples of adults with ID were used to demonstrate skills within each stage. At the beginning of the session, the research was introduced, and explanatory statements and consent forms were distributed. The support workers were also asked to complete a questionnaire that pro- vided background information. During this session, support worker pairs were identified for assignment to the same adult with disability. After the session, support workers were asked to complete the checklist on that adult without discussion with the other support worker also completing a checklist for the same adult. Completing the checklist required that for each item within each stage, the support worker indicated if the behaviour had been ‘observed’ or ‘not observed’. At the end of 2 weeks, they submitted the checklist to the researchers, who then assigned a code and de-identified it prior to data entry.

Completed Triple C checklists were used by two of the researchers to assign a stage, according to Bloomberg & West (1999), using a consensus process; that is, two of the researchers jointly viewed each completed checklist and assigned a stage.

Twenty adults from two participating disability services who had consented to a second stage of the study were observed individually by the researchers working in pairs (all are experienced speech-language pathologists). Observations occurred in the adult’s home or day service during routines, including meals, programmed activities (e.g. music programme, cooking and art) and leisure over a 2–3-h period. Notes on salient communication behaviours were made. Based on these observations, an estimate was made of the person’s highest level of communica- tion by using the Triple C stages, through a consensus process between the two observing researchers.

Results

Support worker agreement

Support workers were assigned as either first or second observers for the purpose of data analysis. Those support workers who completed checklists for more than one target adult were alternatively assigned as first or second observers across the adults. Checklists were obtained from two support workers for 68 of the participating target adults. Agreement for each item was determined by calcu- lating across adults with ID the number of agree- ments, divided by number of agreements plus disagreements and multiplying by 1 to yield per- centage scores. These ranged from 63% to 95% (mean = 85%) for Stage 1/2, from 7 % to 94% (mean = 81%) for Stage 3, from 73% to 95% (mean = 83%) for Stage 4, from 69% to 92% (mean = 84%) for Stage 5, and from 76% to 97% (mean = 87%) for Stage 6.

The researcher consensus coding indicated that for four pairs of checklists, a stage could not be assigned for at least one of the checklists because the data failed to reveal an interpretable pattern. These pairs were deleted from the analysis to deter- mine agreement for stage assignment. The number of completed checklists that were assigned to each stage across the two support workers is shown in Table 1. Agreement between researcher stage assign- ment based on checklists completed by the first versus second support worker was determined using Cohen’s kappa, which yielded a moderate to high coefficient: k = .63 (P < . 1). Table 1 also indi- cates the relatively even spread of checklists that

Table 1 Number of participants assigned to each of the Triple C

stages based on support worker 1 and support worker 2 checklists

Stage assignment

Stage Support worker 1 Support worker 2

1/2 10 (16) 12 (19) 3 14 (22) 12 (19) 4 12 (19) 16 (25) 5 16 (25) 13 (20) 6 12 (19) 11 (17)

Figures in brackets are percentages based on n = 64.

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Table 2 Factor analysis communality scores and factor loadings for support worker 1 and 2 data

Support worker 1 Support worker 2

Stage Communality Factor loading Communality Factor loading

1/2 0.39 0.62 0.59 0.77 3 0.75 0.87 0.72 0.85 4 0.98 0.99 0.87 0.94 5 0.78 0.89 0.78 0.88 6 0.50 0.71 0.41 0.64

were assigned across the five stages for both first and second support worker data.

To determine internal consistency and the con- struct validity of the revised Triple C, analyses were repeated for two sets of data with unreliable data removed, that is, obtained from checklists com- pleted by the first (n = 68) and second (n = 65) support workers for which a stage could be assigned. Internal consistency was determined using KR2 (non-parametric equivalent to Cronbach’s alpha). For the first observer data, the overall KR2 was .97, with those for each stage ranging from .88 to .93. Similar results were obtained for second observer data: the overall KR2 was .97, with those for each stage ranging from .8 to .97.

Construct validity was determined by using stage totals. Preliminary analysis indicated the data from both observers were suitable for factor analysis: Kaiser-Meyer-Olkin (KMO) sampling adequacy was above .7 and Bartlett’s Test of Sphericity was non-significant (P = . ). Data from both data sets were found to be non-normally distributed (Kolmogorov-Smirnov, P < . 1), hence the extrac- tion method for factor analysis chosen was Principal Axis Factoring, as recommended by Fabrigar et al. (1999). For respective sets of data, analysis yielded a one-factor solution (eigenvalue = 3.7) that accounted for 74% and 73% of the variance. Factor loadings and communality scores for each of the stages are presented in Table 2, which indicates that Stages 3 to 5 were the strongest indicators of the factor, while Stages 1/2 and 6 were moderate indicators.

Agreement was determined between stages deter- mined by Triple C checklists completed by support workers and those determined by researcher obser-

vations for the 2 adults with ID. This comparison was conducted for both first and second support worker data. Point-by-point agreement with first support worker data was only 35% and that with the second support worker was 71%. Correlations between the data sets were high for both the first and the second support worker data (r = .79 and .94 respectively), reflecting the fact that differences were never more than one stage.

Discussion

The results of the present study indicated overall high levels of agreement across two support workers about the behaviours of the same individual, that is, in terms of each item within each stage of the checklist. The lowest agreement score was 63% for individual items, with stage averages never falling below 83%. Direct comparison with previous studies is difficult in that they addressed behaviours other than communication (e.g. Harris et al. 1994; Moss et al. 1998) or, in the case of van der Gaag (1989), communicative functions; nonetheless, they provide some means of comparison for observations made by direct care staff. In examining inter-rater reliability on the PAS-ADD checklist for detecting psychiatric disorder, Moss et al. (1998) reported individual item agreement in the form of Cohen’s kappa, with the overall score being quite low at .42, but ranging from .3 to .8. van der Gaag (1989) did not report point-by-point agreement, but rather a correlation of .72 between support worker ratings of communication functions, which, she argued, was indicative of a high rate of agreement.

There are a number of possible reasons for the relatively high levels of agreement across support

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workers found in the present study. First, they received training in the use of the Triple C. This training included information on stages of the Triple C, and working through each item across stages, including the provision of examples through cases presented descriptively and on video. Other researchers reporting on the ability of direct care staff to provide communication information, such as van der Gaag (1989) and Purcell et al. (1999), did not report the provision of training. Moss et al. (1998) suggested that their own poor inter-rater agreement resulted from using untrained raters, as well as failing to provide a guide to rating in the form of a glossary. Some form of training would seem essential given that direct care staff come from diverse backgrounds, often with limited education. Certainly, many of the support workers in the present study had not completed high school, with few reporting tertiary level education. Hence, such direct care staff may be naïve about the behaviours or skills about which they are being asked to report. On the other hand, as argued by van der Gaag (1989), direct care staff develop an expertise about their individual clients as a result of working closely with them on a daily basis and, often, for prolonged periods. This type of expertise may be readily enhanced if the individual is provided the opportu- nity to consider the person he or she is supporting during structured training and if this training targets the required task, such as completion of an assessment checklist.

A second reason for the relatively high levels of agreement on checklist items obtained in the current study may lie in the nature of the task: support workers were asked to report on specific behaviours, rather than to make a judgement about how behaviours relate to particular stages of com- munication. Such judgements would seem more the purview of communication specialists, such as speech-language pathologists, given pre-symbolic communication skills, particularly in adults with significant and often multiple disabilities, are diffi- cult to identify even for professionals (Carter & Iacono 2 2). On the other hand, the information used for such judgements requires observation of an individual across situations and over time, as occurs with other assessment tools developed for individu- als unable to self-report or participate in structured tasks (e.g. Moss et al. 1998). The Triple C, there-

fore, was designed to facilitate the gathering of data by a paid or family carer that can then be used by a speech pathologist or other communication special- ist to make judgements about a person’s level of communication. The PAS-ADD checklist was devel- oped on a similar basis, albeit in relation to behav- iours that could signal psychopathology. As a result, Moss et al. (1998) argued that the item agreement was far less crucial than was the agreement between raters as to those individuals who had scores above the threshold indicative of psychiatric disorder. In the current study, we were concerned about the agreement across the two raters in terms of stage assignment based on completed checklists and determined through a consensus process by two of the researchers. We obtained a moderate to high level of agreement for stage assignment across the two support workers, indicating acceptable agree- ment for the judgements that are based on the support worker data. It should be noted, however, that a few support workers did not provide reliable data. This lack of reliability was evident in checklists that failed to provide a cohesive picture of the adult’s skills (e.g. checking a few items from all stages).

The two sets of data from first and second support workers, with unreliable checklists removed, also yielded similar results in terms of internal consistency and construct validity, as would be expected given the agreement data. Hence, the revised Triple C was found to retain the high level of internal consistency of the first. In addition, the revised Triple C still tapped one underlying con- struct of early communication, but the results for construct validity were clearer than those obtained for the original version. On the basis of analysis of retrospective data, Iacono et al. (2 5) found that the original version tapped only one interpretable factor, argued to be pre-intentional to pre-symbolic ability. The analysis also showed an additional factor onto which Stage 1 loaded highly, but this stage also loaded moderately onto the first factor. In that study, it was argued that the second factor that was tapped by the Triple C may have been more interpretable if the proportion of participants within each stage was better distributed; given that for the retrospective data it was mostly at Stages 3 and 4.

In fact, in the current study, it was found that for the revised version, there was no indication of a

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second factor, with all stages loading moderately to highly onto the one factor. The difference is logi- cally the result of deleting many of the original Stage 1 items and combining the rest with Stage 2 to form a new Stage 1/2, thereby possibly eliminat- ing those that tapped any other factors. In addition, the much smaller sample size of the current study (68 used in the factor analysis for first support worker data) in comparison with that in the original study (n = 172), as well as the more even distribu- tion of communication stages represented (ranging from 16% to 25% across the stages for first and second observer data) may have contributed to this different finding. Given that the factor loadings for all stages, including Stage 6, were moderate to high (above .6), the interpretation of this factor needs to extend from pre-symbolic to symbolic. Stage 6 behaviours reflect established symbolic ability as demonstrated by the use of symbolic forms (spoken, signed or pictured words) (see the Appendix).

A concern with the factor analyses conducted for the present study was the small sample size. Con- vention would suggest the need for much larger samples. According to Stevens (1996), a factor with components comprising four or more components with loadings of .6 or above are considered reli- able, even with small sample sizes. Given that the loadings for all five stages were above .6, given the use of an extraction method that took non-normal distribution into account, and given the similarity of findings across the two support worker data (expected in light of the agreement scores), support for the finding of an underlying single factor would seem strong.

The question of agreement between the stage assignment based on direct researcher observations versus support worker completed checklists was addressed in an attempt to approximate concurrent validity. The results were disappointing, especially for the first support worker data, and reflect previ- ous findings of poor agreement between speech pathology and support worker observations (e.g. van der Gaag 1989; Purcell et al. 1999). The high correlations, however, are indicative that there was never more than one stage difference based on the two data sources. It is tempting to suggest that judgements based on people who could be consid- ered experts by way of professional training and

experience are likely to be the more accurate than those of untrained carers. However, these judge- ments were based on relatively brief observations. Also, although they were conducted in the person’s daily settings, there may have been limited opportu- nity to observe a range of communication behav- iours. There was therefore no strategy for determining the accuracy of the judgements based on the observations beyond observing in pairs and consensus judgements. The challenge in any attempt to determine the concurrent validity of the Triple C is the absence of any formal communica- tion assessment appropriate for people with early communication skills that can provide a basis for comparison. As an example, van der Gaag (1989) and Purcell et al. (1999) used the CASP (Purcell et al. 1999), a tool that assumes at least intentional communication.

Clinical implications

The clinical implications of this study are that if used as designed with collaboration between paid carers and speech-language pathologists, the revised Triple C can be used with confidence. This conclu- sion is made with the caveat that its primary purpose is to provide a means of assessing the communication skills in adults with severe communication impairment such that they are pre-symbolic or have limited symbolic ability. Functionally, these are individuals who have limited speech skills and who may struggle to convey their basic needs and wants, let alone more complex messages such as physical or emotional states. Furthermore, the Triple C was designed as a means of sensitising support staff to their potentially com- municative behaviours, which typically may have gone unrecognised. In a context in which a speech- language pathologist has an opportunity to discuss items and any inconsistencies with a support worker, completion of the Triple C is likely to assist in identifying the communication strengths of these adults.

After completion of the Triple C for a person with ID, the next step is to identify strategies that best support interactions in light of his/her stage of communication. Unfortunately, there is limited guidance for developing such interventions for people whose skills may fall somewhere along

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the unintentional to early symbolic continuum. A recently published manual by Bloomberg et al. (2 4) provides a resource for mapping strategies to Triple C communication stages, however.

Research implications

Further research into the concurrent validity of the revised Triple C, with a larger sample is warranted. Given the lack of assessments appropri- ate for adults at unintentional to early symbolic communication levels, comparisons may need to again be based on direct observations. A combina- tion of prolonged observation and structured sampling (such as used by McLean et al. 1999) may prove to be the only option. Research is also needed on the extent to which completion of the Triple C does in fact assist support workers and family carers to become more aware of the commu- nication ability of persons with ID, and their ability to respond appropriately to their communication attempts.

Acknowledgements

Thanks are extended to the clients and staff of the services that participated in this project.

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Appendix

Revised Triple C stage description

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Accepted 28 July 2008

Communication level Description Example items

Unintentional passive

Unintentional active

Intentional informal

Behaviours produced in response to internal and external stimuli are assigned intent or meaning by a communication partner.

Beginning attempts to act purposefully on objects, with behaviours assigned intention or meaning by a communication partner.

Acting on the environment to create a specific effect, resulting in communication attempts through informal rather than symbolic

Shows an awareness of sounds, particularly voices. Visually follows slowly moving objects or people.

Reaches or moves towards familiar people in familiar situations. Reaches for or looks at an object to indicate preference/choice

Imitates novel behaviours. Uses people to get objects.

means. Symbolic (basic)

Symbolic (established)

Integration of information from each of the senses, trial and error to solve simple problems and uses conventionally understood symbols within limited contexts.

Solving of problems through thinking about them; the person had internal representations and can use symbols in a range of contexts.

Gives or shows an object to a person to obtain an action. Follows a simple instruction out of routine.

Predicts cause/effect relationships. Uses photos, pictures or signs for choice making.