The data reported here were collected over a 23-month period from November 2017 to December 2020.
Screening, recruitment and retention
Of the 11 research sites participating in the study, four had to pause their involvement in the study on one occasion, and one site had to pause involvement on two occasions and eventually discontinued participation. Of the 31 SLTs trained as local collaborators eight left their positions or were unable to continue as local collaborators. All remaining sites paused involvement due to the COVID-19 pandemic from March 2020-October 2020. Four sites volunteered to continue remotely but were unable to recruit any participants. No new participants were recruited after January 2020 and the study was closed in December 2020.
Sixty six people were screened for potential inclusion in the study. Of these potential participants 45 were excluded: 24 did not meet the inclusion criteria, 11 declined to participate, despite being eligible, five declined to participate due to COVID-19 related issues, and five were excluded for other reasons (see the CONSORT flow chart in Figure 1). Twenty one participant dyads, who were deemed eligible and consented to participate in the study, were recruited from seven research sites. Of these, two withdrew from the study immediately after the pre-assessment process reporting that they found the assessment process too challenging. Nineteen participant dyads were randomised, one was discontinued at the onset of the nationwide restrictions related to COVID-19 pandemic and the remaining 18 completed the study. Junior researchers completed the post-intervention assessment with all 18 participant dyads and remained masked to randomisation for 15 of these. On two occasions the participant dyads revealed their allocation prior to assessment.
Demographic and clinical characteristics of participant dyads who completed the study
The characteristics and demographic information of the participants with PPA and their CPs who completed the study are presented in Table 3. All participants with PPA and their CPs spoke English as their language of daily use. The intervention group comprised four men and five women with PPA who had an average age of 72.1 years (range 57- 85 years). Seven of the CPs were spouses, and two were adult children, with an average age of 64.6 years (ranging from 34-80 years). The no treatment control group comprised four men and five women with PPA who had an average age of 71.3 years (ranging from 63-85 years). Eight of the CPs were spouses, and one a close friend, with an average age of 71.6 years (ranging from 69-85 years).
Of the 18 participants, eleven had been diagnosed with a PPA variant and seven with no specific variant specified. Examination of pre-intervention language test data was used to confirm diagnosis of PPA variant in line with the Gorno-Tempini et al2 internationally agreed diagnostic criteria. The data collected confirmed the eleven pre-existing diagnoses and of the seven participants with no specific variant four were diagnosed with a specific PPA variant, whilst the remaining three were judged to present with symptoms consistent with mixed PPA. Of the four given new diagnoses three were given a diagnosis of lvPPA (as there were no signs of speech apraxia, but difficulties in digit span, sentence repetition and word retrieval in the presence of relatively spared comprehension of single words) and one participant was given a diagnosis of nfvPPA (due to the presence of apraxia and agrammatism with relatively intact comprehension). Of the nine participants randomised to the BCPPA treatment arm four had a diagnosis of nfvPPA, three lvPPA and two mixed PPA. In the control arm two had nfvPPA, five lvPPA, one svPPA and one mixed PPA.
All nine dyads with PPA who completed the BCPPA intervention were included in the analysis. The DEMQOL and CCRSA data from one participant randomised to the no treatment control group were excluded due to significant fatigue during post-intervention assessment, resulting in scores at floor. This was not consistent with performance at baseline, nor with other measures taken during the post intervention assessment session.
Acceptability of randomisation
Acceptability to participant dyads
All dyads who participated in the BCPPA intervention arm completed and returned anonymised feedback forms following each intervention session. The following provides a more in depth analysis of the feedback received:
Explanations, format, delivery and expectations of the intervention
Ratings of intervention sessions relating to explanations given, format, and delivery increased as therapy progressed, with session 1 scoring an average of 4.5 compared to an average of 4.7 for session 4 (see Figure 2). Similarly, the participant dyads’ expectations of intervention changed over time. At the start only four of nine dyads reported that session 1 was what they had expected, but by session 4 all dyads reported the session met their expectations. Only one suggestion was made of an addition to the intervention: “to be told how to find alternative words when stuck”.
Usefulness of the intervention
Dyads considered on average 92% of the intervention was useful. Two dyads commented specifically on the utility of watching the video clips of themselves and of the handouts. Video-feedback was considered useful throughout the intervention by 69% of dyads, although one respondent with PPA expressed a preference not to see themself on video.
Improvements as a result of the intervention
Dyads were asked whether each session improved their (i) knowledge and understanding of PPA, and (ii) communication skills. By session 4, 56% of participant dyads rated both domains as improved, and only 11% rated no improvement in either (see Figure 3).
Participant dyads were asked whether therapy was helpful, and if they had made changes in their communication since starting therapy. After session 1, 56% reported it was helpful and 44% that they had made communication changes. By the end of therapy 89% reported that therapy was helpful and 100% that they had made changes in their everyday dyadic communication (see Figure 4).
Acceptability to local collaborators
Local collaborators who delivered the BCPPA intervention completed a fidelity questionnaire for every participant dyad they treated. Table 4 summarises data on aims met, session length, setting, and confidence.
Table 4: Local collaborators’ responses to fidelity questionnaire items on aims met, session length, setting and confidence.
|
Session 1
|
Session 2
|
Session 3
|
Session 4
|
Number of aims met
|
100%
|
100%
|
100%
|
100%
|
Mean length of session in minutes (range)
|
58 (40-70)
|
60 (60)
|
61 (55-65)
|
62 (60-75)
|
Setting delivered
|
7= at their home
2 = hospital outpatients
|
7= at their home
2 = hospital outpatients
|
7= at their home
2 = hospital outpatients
|
7= at their home
2 = hospital outpatients
|
Local collaborators rating of their own confidence in delivering the session
(very confident, confident, somewhat confident, not at all)
|
Very confident: 1 Confident: 6
Somewhat confident: 2
|
Confident: 6
Somewhat confident: 3
|
Very confident: 1 Confident: 6
Somewhat confident: 2
|
Very confident: 1 Confident: 7
Somewhat confident: 1
|
Local collaborators were asked to rate how interesting and enjoyable the dyad found the sessions on a 5-point scale (a little, quite a bit, quite a lot, very much or extremely). Ratings increased as the intervention progressed. In terms of interest of dyads local collaborators rated 55% as finding session 1 ‘very much’ or ‘extremely’ interesting. In terms of enjoyment local collaborators rated 22% of dyads as having enjoyed it ‘very much’ or ‘extremely’ (see Figure 5). By session 4, 89% of dyads were rated by local collaborators on the top two points of both the interest and enjoyment scales (‘very much’ or ‘extremely’).
Local collaborators were invited to make free text comments on the dyads’ enjoyment and interest during the intervention. One local collaborator reported that a CP found the discussion and handouts “a bit infantile” in session 1. Another explained that it was difficult to focus discussion on the CP’s communication skills as well as those of the person with PPA in session 2. One dyad reportedly “really enjoyed the practice tasks” in session 3, and another local collaborator felt that the conversations between the dyad started to feel more natural at this point. Following session 4 two local collaborators reported it had been difficult for a CP to discuss future deterioration.
Local collaborators were also invited to make general comments. One reported a preference for delivering the intervention in a different order than prescribed in the session plans, namely presenting more of the video feedback (session 2) before giving the information (session 1) on how conversation works. Another two commented on technical difficulties experienced when showing video clips. Three commented on session 2 requiring more preparation time than session 1. Following session 4, two local collaborators suggested the dyads they worked with could have benefitted from further practice. In contrast another reported the dyad they worked with could have had one less session.
Summary
Dyads rated explanation, format and delivery of the intervention highly. They rated the intervention as generally useful and after the last session all dyads rated that they had made a change as a consequence of the intervention.
The majority of local collaborators reported feeling confident in delivering the intervention. They reported an increase in the interest and enjoyment of the dyads as sessions progressed. They also reported suggestions for refinement of the intervention.
BCPPA treatment fidelity
Treatment fidelity was 87.2% for the standardised components of the BCPPA intervention. For tailored components it was 63.8%. Average fidelity scores for each of the four sessions, following rater discussion and agreement are presented in Table 5. Inter-rater reliability across the eight observed sessions was 90.74% (range=80.95%-100%) prior to discussion and agreement between raters. A detailed breakdown of fidelity ratings and enactment of the intervention are reported in the paper describing the full fidelity methodology developed for this study33.
Table 5: Treatment fidelity per session, across standardised and tailored components of the BCPPA program
|
Standardised components
|
Tailored components
|
|
Average score / Maximum score
|
%
|
Average score
|
%
|
Session 1
|
16.5 /18
|
91.67%
|
14 /14
|
100%
|
Session 2
|
20 / 26
|
76.92%
|
9.5 / 16
|
59.38%
|
Session 3
|
15 / 16
|
93.75%
|
17.5 / 30
|
58.33%
|
Session 4
|
19 / 22
|
86.36%
|
10 / 20
|
50%
|
Total percentage adherence:
|
|
87.2%
|
|
63.8%
|
In line with recommendations for measuring treatment fidelity this table represents data from a random sample of 20% of sessions, selected using a random list generator to identify two dyads.
Assessment of outcome measures for a full-scale trial
Feedback from local collaborators and junior researchers indicated a preference for the AIQ-2139 over other measures. They reported it was the most meaningful and practicable measure to complete with participants as it linked most closely to the purpose of the intervention (to reduce the impact of PPA on a person’s conversation), and the images made it most accessible. This was the only measure completed with people with PPA where data from all participants could be included (due to fatigue resulting in increased cognitive impairment one participant’s data on the CCRSA and DEMQUAL were excluded), emphasising its accessibility. Importantly, the AIQ-21 has been demonstrated to have statistically significant concurrent validity and good internal consistency, and the prototype has been demonstrated as sensitive to detecting change in people with stroke aphasia following a community intervention39. Thus the AIQ-21 presents a logical choice for a primary outcome measure.
The pre- and post-intervention scores, and the change scores from the five outcome measures are shown in Table 6. The AIQ-21 results demonstrate a mean change score in the intended direction of -3.33 (95% CI -4.26, -2.41) for the BCPPA intervention group, indicating a reduction in the impact of PPA. The mean change score of 2.78 (95% CI -2.11, 7.45) for the no treatment control group indicates an increase in the impact of PPA. On closer examination of the AIQ-21 mean scores, it is apparent there is a large disparity between the BCPPA and the control group mean scores initially, such that the post-intervention score may be attributed to a regression to the mean (the phenomenon of scores being extreme on first measurement, and closer to the mean on second measurement) rather than the impact of the intervention. A future trial may be able to take account of this using a double baseline measure.
Results from the DEMQOL, demonstrate a mean change score in the intended direction of 3.11 (95% CI -3.19, 9.42) in the BCPPA intervention group, and 6.5 (95% CI -1.27, 14.27) in the no treatment control group. This indicates both groups experienced an improvement in quality of life. The CCRSA results demonstrate a mean change score in the intended direction of 3.44 (95% CI -5.31, 12.2) for the BCPPA intervention group and 12.75 (95% CI 5.04, 20.46) for the no treatment control group. This indicates both groups experienced an improvement in communication confidence.
The PSS results demonstrate a mean change score in the intended direction of -0.89 (95% CI -2.44, 0.66) for the BCPPA intervention group and -3.33 (95% CI -6.27,-0.39) for the no treatment group, indicating both groups experienced a reduction in perceived stress. The Zarit Burden Scale results demonstrate a mean change score in the intended direction of -4.78 (95% CI -9.78, 0.23) for the BCPPA intervention group and -5.22 (95% CI -10.27,-0.17) for the no treatment control group, indicating both groups experienced a reduction in carer burden.
Table 6: Outcome measures pre-intervention, post-intervention and change scores for the BCPPA intervention group and no treatment control group
Rater
|
Measure
|
BCPPA (n=9)
|
No treatment control group (n=8 for DEMQOL & CCRSA, n=9 for all other measures
|
|
|
Pre-intervention
|
Post-intervention
|
Change score
|
Pre-intervention
|
Post-intervention
|
Change score
|
PwPPA
|
Aphasia Impact Questionnaire 21 (AIQ-2139)
|
19.78
|
16.56
|
-3.33 (SD: 6.8)
|
11.22
|
14
|
2.78 (SD: 7.48)
|
Dementia Quality of Life Measure (DEMQOL40)
|
87.89
|
92.38
|
3.11 (SD: 9.65)
|
91.38
|
97.88
|
6.5 (SD: 11.21)
|
Communication Confidence Rating Scale for Aphasia (CCRSA41)
|
59.67
|
63.11
|
3.44 (SD: 13.4)
|
63.25
|
76
|
12.75 (SD: 11.12)
|
CP
|
Perceived Stress Scale (PSS42)
|
13.66
|
12.78
|
-0.89 (SD:2.37)
|
14.55
|
11.22
|
-3.33 (SD:4.5)
|
Zarit Burden Scale43
|
27.33
|
22.56
|
-4.78 (SD: 7.66)
|
20.22
|
15
|
-5.22 (SD:7.73)
|
PwPPA= person with Primary Progressive Aphasia, CP= Communication Partner, BCPPA= Better
Conversations with Primary Progressive Aphasia; SD= Standard Deviation.
Goal Attainment Scaling (GAS) scores set and rated by participant dyads in the BCPPA intervention group indicate that of the 30 goals set, 20 were achieved more than expected, seven were achieved, two were achieved much more than expected and one goal was not achieved. The mean baseline score was 36.77 and the post intervention mean attainment score was 59.13, resulting in a mean change score of 22.36 (95% CI 16.75, 27.95). Table 7 provides details of all goals and their attainment, as well as frequency of linked conversation behaviours observed via analysis of pre- and post-intervention video recorded conversations
Each dyad set between two and five goals, resulting in a total of 30 goals. Each goal described a behaviour that participants wanted to consider and change e.g. “To ask more questions”. Some goals comprised change in multiple behaviours e.g. “To use more writing and drawing in conversation” meaning the 28 goals set described a total of 32 behaviours. Two goals set did not align with an observable conversation behaviour, instead targeting participant emotions and were excluded from this behaviour analysis. Of the 32 targeted behaviours, 18 demonstrate a change in the intended direction when comparing frequency of behaviours coded in pre- and post-intervention video recorded conversations. Seven demonstrate no change and 7 demonstrate change in the unintended direction (see Table 7).
Table 7: BCPPA goal attainment and frequency of linked conversation behaviours observed via analysis of pre- and post-intervention video recorded conversations
Dyad
|
Goals agreed by dyad and local collaborator
|
Achievement
|
Baseline Score
|
Attainment Score
|
Change score
|
Corresponding behaviour no. and description (see rating guidance for list of behaviours)
|
Pre-intervention frequency
|
Post- intervention frequency
|
2.01
|
To elaborate more (PwPPA)
To wait or avoid finishing PwPPA’s sentences (CP)
To ask more questions (PwPPA)
To ask more open questions (CP)
|
A+
A+
A+
A+
|
35.78
|
64.22*
|
28.44
|
1 (F)
2 (B)
3 (F)
4 (F)
|
8.33
0
4
0.7
|
6
0
7*
0.7
|
3.01
|
To use gestures when encountering word finding difficulties (PwPPA)
To ask less test questions (CP)
To give additional information around a person’s identity when unable to generate name (PwPPA)
To waiting before offering prompts to help (CP)
|
A
A+
A
A+
|
35.81
|
58.9
|
23.09
|
19 (F)
5 (B)
6 (F)
7 (F)
|
0.33
1.7
0
0.3
|
3*
0.7*
0.33*
3*
|
4.02
|
To use prompt card when needed to help facilitate conversations (PwPPA)
To let PwPPA lead conversations (CP)
|
A+
A++
|
38.76
|
63.3*
|
24.54
|
8 (F)
16 (F)
|
0
0
|
0
0
|
3.03
|
To pause when PwPPA gets stuck on a word and give a bit more time (CP)
To use eye gaze to point, when stuck on a word, to indicate word/topic (PwPPA)
To use hands for gesture/mime to support talking (to prompt self & indicate to others) (PwPPA)
|
A+
A+
A++
|
36.78
|
67.6*
|
30.82
|
7 (F)
24 (F)
20 (F)
|
3
0.33
2.33
|
0
0
12*
|
1.01
|
To choose the topic (PwPPA)
To describe or use gesture if I can't think of the word (PwPPA)
To ask single questions rather than either or questions (CP)
To use shorter sentences (CP)
To ask questions to prompt PwPPA to choose a topic (CP)
|
A+
A
A+
A+
A+
|
35.38
|
63.2*
|
27.82
|
9 (F)
11 (F)
19 (F)
12 (B)
14 (F)
15 (F)
16 (F)
|
3.67
0
0
10.3
0
14.7
7.7
|
3.67
0
0
8.3*
1*
10.3
10*
|
4.04
|
To use a key word then comment based on this, to try and expand responses (to avoid always saying yes / no or agreeing) (PwPPA)
To use a gesture / signal when it’s the end of turn – difficult to know if finished OR if needing time to generate next response (PwPPA)
To prompt / use open ended questions to encourage expanded responses (CP)
|
A
A+
NA
|
37.64
|
43.1
|
5.46
|
17 (F)
18 (F)
4 (F)
14 (B)
|
18.67
0.33
6.3
0
|
16
1*
7*
0.3*
|
8.01
|
To use non-verbal communication / gesture to indicate understanding (PwPPA)
To feel less frustrated in conversations (PwPPA and CP)
To have strategies for managing negotiations in conversation (PwPPA and CP)
|
A+
A
A+
|
36.31
|
59.1
|
22.79
|
20 (F)
|
2.33
|
0.33
|
6.01
|
To use more meaningful gesture in conversation (PwPPA)
To use more writing and drawing in conversation (PwPPA)
To use more key words and automatic phrases in conversation (PwPPA)
|
A+
A+
A+
|
36.31
|
63.7*
|
27.39
|
20 (F)
22 (F)
17 (F)
25 (F)
|
12
0
11.67
3
|
17.67*
0.33*
10.67
3.33*
|
6.03
|
To use intonation more to indicate agreement/disagreement, opinion, feelings and mood (PwPPA)
To use eye gaze to point to support shared attention (PwPPA)
To use props/objects to support conversations (CP)
|
A+
A
A
|
38.2
|
49.02
|
10.82
|
26 (F)
27 (F)
21 (F)
|
0
0.67
2.7
|
0.33*
3.33*
6.7*
|
CP= Communication partner, PwPPA= Person with Primary Progressive Aphasia, NA= Not Achieved, A=Achieved as expected, A+=Achieved more than expected, A++ Achieved much more than expected, *=more than 1 SD from the published t-score mean (Turner-Stokes, 2009), F= facilitator behaviour that enhances the progressivity of conversation, B= barrier behaviour that prevents progressivity, resulting in temporary breakdown of conversation.
Data to inform a sample size calculation
Having calculated an effect size of 0.86 for the AIQ-21 measure, at 80% power and using α 0.05, a sample size of 46 would be required. This was however a small randomised controlled pilot study and the effect size could therefore be inflated. Based on a more conservative effect size calculation of 0.5, at 80% power and using α 0.05, a sample size of 64 participants would be required.
Safety
This was a low-risk behavioural interventions and there were no adverse events or serious adverse events reported.