Review Reports - An Exploratory Randomised Trial of a Self-Managed Home-Based Exaggerated Spatial Cueing Intervention for Handwriting in Parkinson’s Disease

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This paper presents a randomized, exploratory clinical trial to evaluate a novel, home-based handwriting rehabilitation intervention for patients with Parkinson's disease. The study recruited 48 participants with self-reported handwriting difficulties and divided them into two groups: one using paper with divergent lines (with spacing increasing from 10 mm to 13 mm) and a control group using parallel lines (10 mm spacing). Both groups followed a six-week rehabilitation program, with five sessions per week, consisting of writing in a daily journal.

The study found that, regardless of the group, participants showed significant improvements in handwriting speed and amplitude. These improvements were also observed during dual-tasks, suggesting a gain in automaticity. The additional benefits from using the divergent lines were found to be small compared to the control group. The authors conclude that regular, self-managed handwriting practice can lead to significant improvements and that the "exaggerated" cueing system (divergent lines) provides little added benefit.

Advantages of the Study

The intervention is described as a low-resource approach that is self-managed and can be done at home. This makes it accessible and practical for regular monitoring.
The practice led to significant improvements in handwriting amplitude and speed, even when performing a simultaneous cognitive task, which suggests greater automaticity of movement.
The majority of participants (86%) reported perceived benefits, such as better handwriting, greater confidence, and even an improved mood.
No side effects were reported during the study.

Disadvantages and Limitations of the Study

Participant attrition: Several participants were lost to follow-up or dropped out of the intervention, particularly due to the COVID-19 pandemic, which reduced the number of people included in the final analysis.
Limited effectiveness of the "divergent" group: The main advantage of the intervention, the use of divergent lines, proved to be small compared to simple practice on parallel lines. This questions the added value of this specific method.
The authors noted an imbalance between the groups at the beginning of the study, particularly regarding the time taken to complete a sentence, which could potentially bias the results.

Suggestions for Improvement

Increase the sample size: A larger number of participants would increase the statistical power and allow for better generalization of the results.
Improve the recruitment protocol: Implement a system to track people contacted to assess participation rates and reduce selection bias.
Deepen the analysis of divergent lines: Since the study found that the benefits of "exaggerated cueing" are small, future research could explore other forms of visual or auditory stimulation to determine if they might be more effective than simple practice on lines.
Extend the duration of the intervention and follow-up: The rehabilitation lasted for six weeks. Longer-term studies could evaluate the durability of the improvements and their impact on the patients' daily lives.

Author Response

Response to Reviewer 1 Comments
1. Summary
Thank you very much for taking the time to review this manuscript and your helpful and insightful comments. Your appraisal of the ‘advantages of the study’, and ‘Disadvantages and Limitations of the Study’ are consistent with our interpretation and we are therefore eplease that the article conveys this. Please find the response below to ‘suggestions for improvement’ and corresponding revisions/corrections highlighted/in track changes in the re-submitted files.
2. Questions for General Evaluation	Reviewer’s Evaluation	Response and Revisions
Is the content succinctly described and contextualized with respect to previous and present theoretical background and empirical research (if applicable) on the topic?	Can be improved
Are the research design, questions, hypotheses and methods clearly stated? relevant to the research?	Yes
Are the arguments and discussion of findings coherent, balanced and compelling?	Must be improved	Both reviewers identified this as an area for improvement. We have updated the discussion. Highlighting limitations and considerations for future research (see specific responses)
For empirical research, are the results clearly presented	Can be improved
Is the article adequately referenced?	Yes
Are the conclusions thoroughly supported by the results presented in the article or referenced in secondary literature	/Can be improved	We have added Gardoni et al (2025), which a recent reference to support our comments regarding digital technology
3. Point-by-point response to Comments and Suggestions for Authors
Comments 1: Suggestions for Improvement Increase the sample size: A larger number of participants would increase the statistical power and allow for better generalization of the results. With have added a limitation that generalizability is limited due to sample size: There are several factors that should be considered when interpreting our findings. Firstly, the *relatively small sample size limits generalizability….* (page 11, line 367) Improve the recruitment protocol: Implement a system to track people contacted to assess participation rates and reduce selection bias. We have added further comments on the potential of selection bias in those recruited from Parkinson groups ….’It is also important to note that practical reason meant we were unable to assess eligibility of all those attending Azione Parkinson’s, and thus determine the extent of selection bias may have been present in those recruited through this route….’ (page 12, line 370) Deepen the analysis of divergent lines: Since the study found that the benefits of "exaggerated cueing" are small, future research could explore other forms of visual or auditory stimulation to determine if they might be more effective than simple practice on lines. We agree and have added the following, suggesting that digital technologies could offer ways to deliver other/combine methods of cueing: Furthermore, consideration should be given to the use of digital technologies. Internet-enabled touch screen devices could provide additional functionality such as enabling a variety of adaptable spatial and temporal cues for training, and a means for remote monitoring, assessment, feedback and progression. Indeed, Gardoni et al[29] recently demonstrated a commercially available tablet and stylus could be used to analyse the repetitive cursive loop task, and handwriting speed and amplitude. (page 11, line 360) Extend the duration of the intervention and follow-up: The rehabilitation lasted for six weeks. Longer-term studies could evaluate the durability of the improvements and their impact on the patients' daily lives

We agree and have expanded the following to the limitation section to include: ….Therefore, further research is required to assess sustained benefit, which should also consider impact on daily lives….(page 12, line 377)

Reviewer 2 Report

Comments and Suggestions for Authors

The manuscript presents an exploratory randomized trial on a self-managed, home-based handwriting intervention for people with Parkinson’s disease. The topic is relevant and clinically important, since micrographia is a disabling feature and treatment options are limited. The study is well designed for its exploratory nature, with assessor blinding, high adherence, and no adverse events reported. The findings are encouraging, showing improvements in handwriting amplitude, speed, and self-perceived difficulties, all of which are meaningful for patients.

Some points could, however, be strengthened. The study relies on paper-and-pencil measures, which are acceptable in clinical rehabilitation but less precise than digital methods; it would be important to acknowledge this limitation and suggest that future work consider digitizing tablets or image processing to increase reproducibility. The additional effect of the “diverging” cueing compared to parallel lines was small, and the discussion might elaborate more on possible reasons, such as a ceiling effect or the general benefits of daily practice rather than the cueing strategy itself. The relatively small sample size also limits generalizability, and this should be highlighted. Minor language editing would improve clarity, particularly in the Results and Discussion, and consistency of units (for example, reporting millimeters for amplitude) should be ensured throughout. Finally, since the training was conducted at home without supervision, participants may have worked under very different conditions regarding seating, desk height, lighting, or posture. This variability could have influenced performance and should be recognized as a limitation, with the suggestion that future studies provide clearer guidelines or explore remote monitoring to standardize conditions.

Overall, the manuscript makes a valuable and interesting contribution for clinicians and rehabilitation specialists. With minor revisions and clearer acknowledgment of these limitations, it can be suitable for publication.

Author Response

Response to Reviewer 2 Comments
1. Summary
Thank you very much for taking the time to review this manuscript and for your helpful and insightful comments. Please find responses below and the corresponding revisions/corrections highlighted/in track changes in the re-submitted files, which we hope have addressed your comments and believe they have improved the manuscript.
2. Questions for General Evaluation	Reviewer’s Evaluation	Response and Revisions
Is the content succinctly described and contextualized with respect to previous and present theoretical background and empirical research (if applicable) on the topic?	Yes
Are the research design, questions, hypotheses and methods clearly stated? relevant to the research?	Yes
Are the arguments and discussion of findings coherent, balanced and compelling?	Can be improved	Both reviewers identified this as an area for improvement. Please see the response to specific comments, which we believe have improved this section.
For empirical research, are the results clearly presented	Yes
Is the article adequately referenced?	Yes
Are the conclusions thoroughly supported by the results presented in the article or referenced in secondary literature	Yes
3. Point-by-point response to Comments and Suggestions for Authors
The study relies on paper-and-pencil measures, which are acceptable in clinical rehabilitation but less precise than digital methods; it would be important to acknowledge this limitation and suggest that future work consider digitizing tablets or image processing to increase reproducibility. Many thanks for raising this point, we agree that use of digital technology may have several benefits in both intervention delivery and outcome assessment and have added the following: Furthermore, consideration should be given to the use of digital technologies. Internet-enabled touch screen devices could provide additional functionality such as enabling a variety of adaptable spatial and temporal cues for training, and a means for remote monitoring, assessment, feedback and progression. Indeed, Gardoni et al[29] recently demonstrated a commercially available tablet and stylus could be used to analyse the repetitive cursive loop task, and handwriting speed and amplitude. (page 11, line 360) The additional effect of the “diverging” cueing compared to parallel lines was small, and the discussion might elaborate more on possible reasons, such as a ceiling effect or the general benefits of daily practice rather than the cueing strategy itself. Many thanks, we postulated that this could be due to progressive micrograpthia not being predominant in our cohort or that subtle difference between the interventions. However, we agree that there could also be a ceiling effect and have added this consideration. ….. This subtle increased stimulus may have also contributed to the minimal differences found between groups, alongside a ceiling effect in those who’s handwriting amplitude achieved that of the spatial cues. Broder et al[28] investigated the acute effect of a 10mm divergence, future work could consider the influence of the size of the exaggerated stimulus…..(page 11, line 326) The relatively small sample size also limits generalizability, and this should be highlighted. We agree and have made a specific statement to this effect in the limitations There are several factors that should be considered when interpreting our findings. Firstly, the *relatively small sample size limits generalizability….* (page 11, line 367) Minor language editing would improve clarity, particularly in the Results and Discussion, and consistency of units (for example, reporting millimeters for amplitude) should be ensured throughout. Apologies we have reproof read the manuscript and hope to have improved clarity Finally, since the training was conducted at home without supervision, participants may have worked under very different conditions regarding seating, desk height, lighting, or posture. This variability could have influenced performance and should be recognized as a limitation, with the suggestion that future studies provide clearer guidelines or explore remote monitoring to standardize conditions. We agree that to guidelines may support participation and, linked to comment above, briefly discuss how digital technologies may also support this (see response above) …Whilst, the pragmatic nature of the intervention has these benefits, it may have contributed to variability in the training response, as people chose when and how to engage with the daily handwriting practice. Future studies should consider co-developing guides and materials to support long-term participation. Furthermore, consideration should be given to the use of digital technologies…..(page 11, line 356)

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

The paper exhibits a high level of clarity and organization, with a particularly intriguing central concept. In comparison to the previous version, the author has incorporated explanations pertaining to tasks and standard assessments across the entirety of the document.