Table 2 Acceptance, use competence, and use of the AAC system

Acceptance of the caregiver towards the new AAC system

 1. I am motivated to use the new AAC system with the person.

3.37

0.90

3.15

1.00

0.025*

 2. I accept that the person is unlikely to speak and will require this or other AAC systems for the foreseeable future.

3.34

1.06

3.28

1.00

0.382

 3. I do not find it frustrating to use the new AAC system with the person.

3.31

1.02

3.07

1.10

0.035*

 4. I can realistically assess what impact the new AAC system could have on the person’s quality of life.

3.10

0.95

2.84

1.04

0.024*

 5. I believe that the person needs the new AAC system in order to communicate more effectively with me.

3.05

1.20

3.10

1.13

0.886

Subscale sum scores

3.23

0.77

3.09

0.85

0.156

Acceptance of the AAC user towards the new AAC system

 1. The person prefers the new AAC system over other, simpler forms of communication such as vocalisations, gestures, and less complex forms of communication.

1.84

1.25

1.63

1.10

0.172

 2. The person had a say in selecting the new AAC system.

1.81

1.44

1.78

1.38

0.878

 3. The person appears to value the new AAC system.

2.61

1.24

2.47

1.09

0.213

 4. When using the new AAC system, the person does not appear to get frustrated as often as with other forms of communication.

2.25

1.23

2.09

1.16

0.217

 5. The person demonstrates a sense of ownership of the AAC device.

2.57

1.48

2.23

1.50

0.062

Use competence of the caregiver and the AAC user

 1. The person is usually more successful communicating with the new AAC system than with other forms of communication.

2.35

1.22

2.24

1.14

0.361

 2. The person conveys his/her feelings, wishes and needs more effectively with the new AAC system than with other forms of communication.

2.03

1.18

1.89

1.22

0.328

 3. The person is physically able to use the new AAC system. For example, he/she can press the buttons/show symbols/perform gestures.

3.28

0.94

3.15

1.04

0.253

 4. The person is able to use the new AAC system independently without needing help.

2.19

1.28

1.85

1.27

0.024*

 5. The person understands how to use the new AAC system.

2.77

1.15

2.57

1.02

0.057

 6. It is easy to programme messages on the AAC device (e.g., on a voice output device) or to design content for the AAC device (e.g., new symbol cards, me-book content).

2.78

1.13

2.71

1.13

0.550

 7. The new AAC system enables the person to communicate for a variety of purposes such as making requests, choices, responding to questions, and disagreeing.

2.53

1.18

2.34

1.18

0.149

Use of the new AAC system in everyday life

 1. I encourage the person to use the new AAC system both at home and in the community.

3.06

1.08

2.77

1.09

0.009*

 2. I make sure the new AAC system is available to the person whenever possible.

3.36

0.94

2.82

0.98

< 0.001**

 3. There are reasons for the person to use the new AAC system frequently at home and elsewhere.

2.60

1.19

2.47

1.17

0.307

 4. The person has numerous opportunities to use the new AAC system.

2.91

1.01

2.54

1.03

0.001*

 5. It is easy to use the new AAC system in daily interactions with the person.

2.63

1.04

2.19

0.98

< 0.001**

 6. The use of the new AAC system is more appropriate than other forms of communication the person has previously used.

2.65

1.11

2.56

1.07

0.500

 7. Communication with the person is usually more effective when he/she uses the new AAC system rather than other forms of communication.

2.37

1.13

2.17

1.10

0.167