Individuals with intellectual disability (ID) often struggle to obtain independence, and learn the skills required for daily living (Westling and Fox 2004). The development of daily living skills (e.g., navigating public transit, food preparation, and hygiene) is therefore an important treatment priority for people with ID (Matson, Dempsey, and Fodstad 2009; Matson, Rivet et al. 2009; Neef et al. 1978). Daily living skills are considered essential to enhancing independence. Regardless of whether an individual has mild or severe intellectual disability, the acquisition of these skills may lead to increased independence and is thought to reduce passivity and learned helplessness (Parmenter 1993). Over the past four decades, a considerable amount of attention has been directed towards developing effective instructional strategies for teaching daily living skills to individuals with intellectual and developmental disabilities (e.g., Westling and Fox 2004).

One instructional approach that has been used to promote daily living skills is in vivo-instruction (e.g., Cuvo and Klatt 1992). In-vivo instruction involves the use of natural stimuli in the criterion environment. For example, Morrow and Bates (1987) taught people with severe ID to do their laundry using clothes in a real laundry room. A potential benefit to in-vivo instruction is that it might promote the use of the skills in natural environments and reduce the need to program for generalization using additional instructional techniques (Hutcherson et al. 2004; Stokes and Baer 1977). However, there are often logistical complications involved with in-vivo instruction, including scheduling, funding, and time constraints that may reduce the feasibility of implementation (Mechling and Gast 2003; Wissick et al. 1999). Additionally, it might also be inconvenient or unsafe to teach a person skills during real live situations (e.g., teaching street crossing in vivo before a certain level of mastery).

A second instructional approach for teaching daily living skills is the use of video-based instruction (VBI; Rayner et al. 2009; Sturmey 2003). VBI involves the learner observing a video recording of the target skill occurring in the natural environment and then providing opportunities for the person to imitate the target behaviors or skills that were shown in the video (Mechling et al. 2005). VBI has been successfully used to teach food preparation (e.g., Rehfeldt et al. 2003; Sigafoos et al. 2005), shopping and self-care skills (e.g., Norman et al. 2001).

A third approach for teaching daily living skills involves the use of computer-based intervention (CBI; Ramdoss, Lang et al. 2011; Ramdoss, Mulloy et al. 2011). In CBI, like VBI, the computer delivers instruction by presenting visual and audio stimuli related to the target skill. However, unlike VBI, CBI also allows the learner to interact with the program using external hardware devices such as touch screens, trackballs, switches, keyboards, or scanners (Mechling et al. 2003). This interaction with the learner is viewed by some as one way of providing more sophisticated instructional components than can be provided via VBI; such as, specific reinforcement contingencies, corrective feedback, and tailored prompting hierarchies (Higgins and Boone 1996; Mechling et al. 2005).

These various instructional approaches have been addressed in several previous literature reviews focused on strategies to promote daily living skills for individuals with ID. Mechling (2008a) conducted a literature review of studies focusing on teaching cooking skills to individuals with moderate intellectual disability, and found that instructions and prompting delivered by picture-based systems, handheld personal computers, auditory systems, and VBI have been effective. Morse et al. (1996) reviewed studies that taught grocery shopping skills to individuals with ID and found that verbal instruction with modeling and role play, videotape and slide show examples, serial and concurrent sequencing strategies, and backward chaining were effective teaching procedures. Finally, Palmen et al. (in press), reviewed the literature aimed at improving adaptive skills in high-functioning young adults with autism spectrum disorders (ASD) and found that a variety of high- and low-technology instructional modalities have been used with success to teach social, vocational, and domestic skills. In addition to previous reviews related to daily-living and adaptive skills in individuals with ID, there have also been several reviews on the use of CBI in the treatment and education of individuals with ASD. In one such review, Ramdoss, Lang et al. (2011) concluded that CBI is a promising intervention approach for improving communication skills of people with ASD. Similarly, Ramdoss, Mulloy et al. (2011) reviewed evidence suggesting that CBI is an effective means of academic instruction for students with ASD.

A systematic review of the use of CBI to teach daily living skills to individuals with ID, however, has not been previously conducted. Given the importance of daily living skills and the obstacles often inherent to in-vivo instruction (e.g., cost and logistical difficulty of moving students from schools to criterion community settings) such a review would appear to be warranted. This current review has three aims: (a) to evaluate and synthesize the evidence-base, (b) inform and guide practitioners interested in the use of CBI and (c) stimulate and guide future research aimed at using CBI to promote daily living skills.

Method

Studies were included in this review based on pre-determined inclusion criteria. Each included study was analyzed and summarized in terms of (a) participant characteristics, (b) daily living skill(s) targeted, (c) pertinent details regarding the computer hardware and software, and (d) outcomes of CBI.

Search Procedures

Systematic searches were conducted in four electronic databases: Education Resources Information Center (ERIC), Medline, Psychology and Behavioral Sciences Collection, and PsycINFO. The keyword fields in all four databases were searched using the terms (intellectual disab*) or (developmental disab*) or (mental retardation) or (autis*) or (asperger*) or (PDD*) and (independent) or (daily living) or (life skills) or (self-help) or (hygiene) or (adaptive) and (computer) or (computer based) or (computer assisted). The search was restricted to articles written in English and published after 1990 in peer-reviewed journals. Following the electronic database searches, the reference sections of studies meeting the inclusion criteria (see below) were searched to identify additional studies for possible inclusion.

Inclusion and Exclusion Criteria

In order to be included in this review, a study had to meet three criteria. First, an intervention delivered via a computer software program must have been evaluated. Second, the study had to contain at least one participant with an ID (i.e., IQ < 70). Third, a study must have measured at least one dependent variable pertaining to a daily living skill. For the purposes of this review, daily living skills were defined as skills that are essential to functioning in every-day life (e.g., hygiene and dressing) and/or taking part in community activities (e.g., shopping in a grocery store and ordering a meal in a restaurant).

Studies were excluded from this review for the following reasons. First, due to immense change in the capacity and diversity of applications of computer technology over the past two decades, studies published prior to 1990 were excluded in order to focus on more contemporary technology. Second, studies in which computers were used solely as a means to deliver reinforcers (e.g., Soares et al. 2009) or deliver VBI (e.g., Sigafoos et al. 2005) were excluded. Finally, computer programs that allowed only minimal input and control (e.g. play, stop, next) were considered video technologies, analogous to DVD players, and were excluded (e.g., Kinney et al. 2003).

Data Extraction and Coding

Initially 108 studies were retrieved from this electronic database search. The abstracts of these 108 studies were then screened against the inclusion and exclusion criteria. Ultimately, 11 studies were included in the review. The 11 included studies were summarized in terms of: (a) participant characteristics, (b) daily living skills targeted, (c) details regarding the computer-based instruction, and (d) intervention outcomes (including any relevant social validity or treatment acceptability data). Outcomes of CBI on daily living skills were summarized as either “positive”, “mixed”, or “negative” using criteria presented by Machalicek et al. (2007). A classification of “positive” indicated that all participants registered gains on all dependent measures. A classification as “mixed” indicated that the participant(s) improved on some dependent measures and remained constant or declined on the others. “Mixed” was also used if some participants improved, but others did not. Classification as “negative” indicated that the participants’ independent and daily living skills declined or remained constant on all dependent measures (i.e., there was no improvement).

Inter-rater Agreement

A summary was produced for each of the 11 included studies by the first author. The accuracy of these summaries was then assessed by a co-author using a checklist that included the initial summary of the study and five questions regarding various details of the study. Specifically: (a) Is this an accurate description of the participants? (b) Is this an accurate description of the daily living skills targeted? (c) Is this an accurate description of the intervention? And (d) Is this an accurate description of the results? In cases where the summary was not considered accurate, the summary was edited to improve accuracy. This process was continued until 100% agreement regarding the accuracy of the summaries was reached. The resulting summaries were then used to create Table 1. This approach provided a measure of inter-rater agreement on data extraction and analysis. There were 44 items on which there could be agreement or disagreement (i.e., 11 studies with 4 questions per study). Initial agreement was obtained on 40 items (90%) and then corrected until there was 100% agreement.

Table 1 Summary of Included Studies
Full size table

Results

Table 1 summarizes the 11 studies included in this review in terms of: (a) participant characteristics, (b) daily living skills targeted, (c) the CBI methods and materials, and (d) outcomes.

Participant Characteristics

Collectively, the 11 studies provided CBI to a total of 42 participants. Twenty-four (57%) of the participants were male and the remaining 18 (43%) were female. The ages of the participants ranged from 7.7 to 58 years (M = 19.1 years). In addition to ID, four participants had a diagnosis of autism (Ayres et al. 2009; Hutcherson et al. 2004) and one study involved a participant with the diagnosis of PDD-NOS (Mechling and O’Brien 2010). Although IQ scores were rarely reported, the participant descriptions provided by the authors of the included studies suggest that the majority of the participants could best be described as having moderate ID. One study included participants described as having moderate to severe ID (Mechling and Cronin 2006).

Hardware and Software Programs

A variety of hardware devices were used including headphones, digital video camera, auto-zoom focus camera, scanner, and external hard-drives. Participants used a variety of external devices to provide input during CBI. In six studies, participants operated mouse/trackballs and interacted using the click function (Ayres and Cihak 2010; Ayres et al. 2006; Ayres et al. 2009; Hansen and Morgan 2008; Hutcherson et al. 2004; Mechling and Gast 2003). A touch-screen was used in four studies (Davies et al. 2003; Mechling 2008a, b; Mechling et al. 2002; Mechling and O’Brien 2010). One study involved the participants using speech-generating devices to make selections (Mechling and Cronin 2006).

Six studies used software programs that were specifically designed for the purposes of their intervention. Three of these studies used the program “Project Shop” (Ayres et al. 2006; Hansen and Morgan 2008; Hutcherson et al. 2004) and two used a program named “I can! Daily Living and Community Skills” (Ayres and Cihak 2010; Ayres et al. 2009). One study used a program named “ATM Sim” (Davies et al. 2003). Five studies used commercially available multi-authoring tools such as “Hyper Studio (Mechling and Cronin 2006; Mechling and Gast 2003; Mechling 2008a, b; Mechling et al. 2002) and Microsoft PowerPoint and Windows Movie Maker (Mechling and O’Brien 2010). Software programs that are specially designed to teach daily living skills (i.e., Projectshop, I can! Daily living and community skills, and ATM Sim) were no longer commercially available at the time this review was conducted and the operating system and other system requirements are not clearly identified.

Target Skills

Across studies, a variety of dependent variables associated with daily living skills were examined (i.e., grocery shopping, preparing food, using automated banking machines [ATM], using debit machine, placing orders in fast food restaurants, and navigating public transport). Five studies examined the effectiveness of CBI on teaching some aspects of grocery purchasing (Ayres et al. 2006; Hansen and Morgan 2008; Hutcherson et al. 2004; Mechling and Gast 2003; Mechling et al. 2002). For instance, Mechling et al. (2002) examined the efficacy of CBI on reading grocery aisle signs. Hutcherson et al. (2004) and Mechling and Gast (2003) used CBI to teach grocery item selection. Hansen and Morgan (2008) measured the effectiveness of CBI on teaching a 5-step purchasing sequence that included, among others, selecting the checkout line and placing the items on the conveyor. Finally, Ayres et al. (2006) used CBI to teach a strategy for determining how much money to hand the checkout person (i.e., the dollar amount plus one more dollar to cover the change called the dollar plus strategy).

Two studies examined the effectiveness of CBI on teaching the participants to set the table and simple meals (i.e., Ayres and Cihak 2010; Ayres et al. 2009). One study used CBI to teach the use of a debit card (Mechling 2008a, b) and another study used CBI to teach the use of an ATM machine (i.e., Davies et al. 2003). Mechling and Cronin (2006) used CBI to teach how to place an order in fast-food restaurants. Finally, a study conducted by Mechling and O’Brien (2010) used CBI to train students to use public bus transportation.

Outcomes

Thirty-nine of the 42 participants (93%) acquired the targeted daily living skill via CBI. In all of the studies baseline was conducted in the criterion environment (e.g., at the real grocery store, bus stop, or restaurant in which the behavior was expected to occur once taught) and CBI was implemented in a separate instructional setting (e.g., home or school). Following CBI outcome measures were again taken in the criterion environment. The most common approach used to promote generalization during CBI was to use videos or images taken directly from the criterion environment to make the simulated training setting as similar to the criterion setting as possible. For example, Mechling and Cronin (2006) created a video by recording within the actual grocery store where the participants were going to shop and that video was then used for the CBI simulation. Out of the 11 studies, 8 reported positive outcomes for all participants, and three reported mixed outcomes (i.e., Ayres et al. 2006; Mechling and Cronin 2006; Mechling and O’Brien 2010).

To illustrate a mixed-outcome study, Ayres et al. (2006) found that CBI was effective in teaching dollar-plus purchasing strategy to three out of their four participants. Throughout the study, the one participant without positive outcomes (Emily) exhibited variable performance during baseline in-vivo probes and during computer instruction sessions. She had a medical condition that occasionally resulted in the interruption of the session to provide her with medication and rest. Even though Emily reached a high of 100% correct performance during one session, her medical conditions might have prevented her from concentrating on given tasks and inhibited her from stabilizing her performance. As another example, two of the three participants in the Mechling and Cronin (2006) study showed an immediate increase in their correct use of their AAC device following CBI, but one participant did not use the AAC device during the first generalization probe session. Instead of using the AAC device, this participant (Chris) reverted back to an old form of communication by holding up one finger to indicate his food choice. As suggested by the study authors, allowing Chris to select his own communication device might have helped increase his frequency of device use. Finally, in the study conducted by Mechling and O’Brien (2010), all three participants met the criteria for pushing “request to stop bus-signal” during CBI session. However, only two of those participants generalized the skills with 100% accuracy during all of the in-vivo sessions. The remaining participant did not generalize the skill in the first generalization in-vivo condition following CBI. Instead of pushing the request to stop bus signal button independently, she continued to require a prompt from teacher.

Six of the included studies assessed the maintenance of acquired skills (i.e., Ayres and Cihak 2010; Ayres et al. 2009; Hansen and Morgan 2008; Mechling and Cronin 2006; Mechling 2008a, b; Mechling and O’Brien 2010). Follow-up probes were conducted from 2 weeks to 15 weeks following the CBI. In all of these six studies, target skills were maintained at similar levels to the final intervention phase.

Discussion

Our systematic search yielded 11 studies involving the use of CBI to teach daily living skills to 42 individuals with ID. The current research base must be considered limited because of the small number studies (n = 11) and participants (n = 42). Additionally, the diversity of the participants in terms of age, the range of skills targeted for instruction, and the various types of CBI programs that were implemented prevent firm conclusions regarding the characteristics of participants most likely to benefit from CBI and the types of daily living skills most efficiently taught via CBI. However, because more than 93% of the individuals that participated in these studies acquired the targeted skills, our analysis of these studies suggests that CBI is a promising intervention strategy for teaching daily living skills to individuals with moderate ID. In terms of the goals of this review, to inform and guide practitioners and identify directions for future research, a few important considerations emerge.

First, the software programs specifically designed for instruction of individuals with ID (i.e., Project shop, I can! Community and daily living, and ATM Sim) appear to no longer be commercially available for practitioners. Although this is disheartening, five studies utilized programs designed for general purposes that can be adapted to deliver CBI and are currently being manufactured and marketed (i.e., Hyperstudio, MS PowerPoint, and Windows Movie maker). As stated in previous reviews involving CBI (e.g., Ramdoss, Lang et al. 2011), these more general purpose software programs require the teacher or parent to develop the instructional materials. As such, the quality of the instructional materials and the success of the intervention are likely to depend more on the quality of presentation and the knowledge of the curriculum developer than on the software itself.

Second, given the need for interventions to be efficient and accessible to practitioners in order to be socially valid (Lang et al. 2010), the lack of commercially available software programs for this purpose must be considered a potential impediment to the adoption and use of CBI by practitioners, and there would seem to be a need and market for this type of specialized software. Future software designed for this purpose should consider the qualities of effective instruction. It is important to remember that CBI is an intervention delivery mechanism not an intervention within itself (Ayres and Cihak 2010). As recommended by Higgins and Boone (1996), researchers should continue to investigate and empirically validate the effective components of educational software programs (e.g., varied presentation, portability, naturalistic stimuli, user interface) in order to inform the development of specialized educational software for individuals with ID.

Third, hardware plays an almost equally important role in the usability and versatility of CBI. Recent technological advances in hardware would seem to have set the occasion for continued evolution of CBI and, given the success of the studies reviewed here, research involving new hardware appear warranted and promising. For example, only a few studies have been conducted using hand-held computer devices to teach individuals with developmental and intellectual disabilities (e.g., Davies et al. 2003). Considering the emerging utility of touch-screen interface technology and the shrinking size of computers (e.g., iPod-touch, iPad), the development of special education applications for these devices would seem likely. One concern regarding CBI is the generalization of skills from the computer environment to the natural criterion environment. These more portable and dynamic devices could be used to covertly prompt and teach within the natural environment and reduce concerns related to generalization across settings. For example, a child who uses a handheld computer to receive promotes related to grocery shopping may be more likely to use the skill in the grocery store following intervention than a child who uses a similar program to teach grocery shopping skills in their classroom (Stokes and Baer 1977).

In this review, we identified a variety of daily living skills that have been taught with CBI. There are several factors that should be considered when selecting which daily living skills to target for instruction. First, it is important to determine what other skills may be needed in order for the individual to actually use the target skill in the community. For example, teaching a person to checkout in a grocery store or order in a restaurant are only functional skills if the individual is able to get to the locations. Second, as skills such as ATM use, transportation, and exchange of money are taught, it is important to be sure that they are simultaneously learning the safety skills required to prevent victimization. For example, an individual who is taught to withdraw money from an ATM should also be taught under what conditions doing so might be unsafe and not to give money to strangers under suspicious circumstances (Mechling 2008b). Finally, practitioners and researchers interested in the use of CBI should be careful to ensure that a chosen skill is taught together as a part of “skill clusters” rather than an isolated skill (Mechling and Gast 2003). For instance, five studies demonstrated that individuals were able to acquire skills that are essential for grocery purchase. However, these studies have focused on different aspects of grocery skills and taught them as an isolated skill (e.g., reading aisle signs, item selection, 5-step purchasing sequence, and paying the amount using dollar-plus strategy). In some cases, this may leave open the possibility that the desired terminal skill purchasing groceries may remain out of reach.

In conclusion, the current research base is encouraging and it appears that the accelerating development of technology is benefiting individuals with ID. However, more research into CBI is needed before this approach could be viewed as well-established for teaching daily living skills to individuals with ID.