Virtual Reality Driving Simulator: Investigating the Effectiveness of Image–Arrow Aids in Improving the Performance of Trainees

Round 1

Reviewer 1 Report (Previous Reviewer 1)

Comments and Suggestions for Authors

1. The abstract states that "G1 performed significantly better than G2 and G3" but lacks specific numerical data on core metrics.
2. Section 3.2 notes that "driving and gaming experience" was recorded but does not verify whether these potential confounders differ significantly across groups. 
3. Section 3.1.2 mentions the virtual environment includes "no traffic," only road infrastructure. This design may underestimate cognitive demands in real driving.

Author Response

Please see attached PDF file for responses to reviewer

Author Response File: Author Response.pdf

Reviewer 2 Report (Previous Reviewer 2)

Comments and Suggestions for Authors

The study tackles a relevant and interesting topic—improving novice driver training through VR aids.

• The research design description is inconsistent (Latin-square vs separate groups) and needs clarification.

• Reported speed zones in m/s are implausible for the context; unit accuracy should be ensured.

• Lack of traffic in the simulator reduces ecological validity, especially for lane-change and signal tasks.

• The “errors + time” composite is mentioned but not clearly defined or analyzed.

• Statistical reporting is incomplete: post-hoc tests, effect sizes, and assumption checks are not provided.

• The questionnaire validity section is not supported with a correlation matrix, and table numbering is inconsistent.

• Cognitive load is central to the argument but not measured with a validated instrument.

• Participant baseline characteristics (driving and VR experience) are noted but not analyzed, leaving “novice driver” status unclear.

• The operationalization of “errors” is vague, with insufficient detail on detection and weighting.

• Hardware and procedural details (familiarization, motion sickness handling) are limited.

Comments on the Quality of English Language

The English is understandable, but phrasing is often awkward and grammar inconsistent. Careful proofreading and language polishing would improve readability and professionalism.

• Editorial issues remain (placeholders, broken citation markers, inconsistent numbering).

• Language is generally understandable but would benefit from polishing for grammar and clarity.

Author Response

Please see attached PDF file for responses to reviewer 2

Author Response File: Author Response.pdf

Reviewer 3 Report (New Reviewer)

Comments and Suggestions for Authors

The paper is about a simulation study about using image-arrow panels in a virtual reality driving simulator.

The literature review is clear, test is well organized, the group size, composition, observations, questionnaires and statistical calculations are well designed.

The reviewer has some recommendations to improve the clarity of presentation.

Although there is a list of abbreviations at the end of the paper, it would be still useful to check and resolve all abbreviations as they first appear (e.g. GPU in line 44, HUD in line 88).

“Image-arrow aids” are the core topic of the paper. They are defined already in the abstract. However, it is only Figure 7, where the reader can have a visual impression of what they are. Please consider inserting an example figure or moving Fig. 7 earlier in the text.

The quality of the photo figures should be improved.

Table 3 and Figure 11. contain the same information. One of them is not necessary.

 

Author Response

Please see attached PDF file for responses to reviewer 3

Author Response File: Author Response.pdf

Reviewer 4 Report (New Reviewer)

Comments and Suggestions for Authors

The manuscript addresses an interesting question by comparing three types of instructional aids in a VR simulator. The reported findings indicate that the image–arrow–text condition (G1) outperforms the alternatives. The exposition is largely clear; however, several aspects require clarification, particularly the scope of randomization and the mutual exclusivity of experimental conditions, along with minor factual and editorial corrections. Implementing the proposed revisions would substantially enhance the manuscript’s clarity and credibility.

1. Randomization
   Please specify precisely what was randomized (“randomizing the order of the scenarios”), given that a single route (~900 m) with nine maneuvers is described. Clarify whether the order of maneuvers, difficulty levels, or other scenario elements were randomized.
2. “Balanced Latin square” and group allocation
   In the current description, the Latin square scheme appears to have been applied to a fixed allocation of 45 participants into three groups (G1–G3), whereas this procedure is typically used to counterbalance the order of conditions in within-subject designs. Please either describe a simple random assignment to the three groups or specify precisely how the Latin square was actually implemented.
3. Units and speed realism
   The limits of 30/60/80 m/s correspond to ~108/216/288 km/h and are not appropriate for school/residential areas. Please standardize units and adopt realistic values (e.g., in km/h) or appropriate m/s equivalents.
4. Correction of instrument description
   The statement “Tachometer: it displays the current speed” is incorrect. A tachometer displays engine revolutions (RPM), whereas a speedometer indicates vehicle speed. Please correct the UI description.
5. Mutual exclusivity of experimental conditions
   The description of G2 includes arrows, which compromises the mutual exclusivity of conditions. Please define the modalities unambiguously:
   G1: image + arrow + text;
   G2: audio + text (no arrows);
   G3: arrow + text (no images or audio);
   and ensure the figures consistently reflect these definitions.
6. Operationalization and error counting
   While examples of errors are provided (e.g., wrong-way driving, collisions, speeding), strict counting rules are not specified. Please add a closed-form definition (e.g., a threshold for speed exceedance counted as one error) to ensure reproducibility.
7. Survey percentages—denominator
   Please clarify whether the reported percentages refer to the full sample (n = 45) or to each group (n ≈ 15). Reporting both n and % for each group or adding a brief methodological note in table/figure captions is recommended.
8. Tone of conclusions
   Consider moderating the categorical phrasing of the conclusions (“G1 is the most effective…”) and explicitly relating them to the study’s limitations (small sample, single route, short-term measurement) to strengthen the interpretation.

 

Comments on the Quality of English Language

The manuscript’s language is intelligible but would benefit from moderate copy-editing to eliminate grammatical slips and refine terminology. Consistent verb tenses are recommended (Methods/Results in the past), as is sharpening technical vocabulary for example, distinguishing between “speedometer” and “tachometer.” Units and numerical formatting should be standardized, typographical errors removed, and overly long sentences tightened. Overall, the text is readable, but professional language editing would substantially enhance clarity and overall readability.

Author Response

Please see attached PDF file for responses to reviewer 4

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report (Previous Reviewer 2)

Comments and Suggestions for Authors

The manuscript has addressed all of my comments and improved its quality significantly.

Reviewer 4 Report (New Reviewer)

Comments and Suggestions for Authors

The authors have addressed most of the earlier recommendations: speed limits have been made realistic (km/h with m/s equivalents), the description of indicators has been corrected (speedometer vs. tachometer), and error definitions have been operationalized in a manner conducive to replication. The results (G1 outperforming G2 and G3 in both error counts and completion time) are presented clearly and consistently. The remaining issues are clarificatory/editorial in nature and can be resolved without new analyses or changes to the protocol.

Scope of minor revisions:

1. Study design and randomization—harmonize the description.
   The response to reviewers explains that the route and maneuver order were fixed, and that the balanced Latin square concerned only the ordering of conditions across groups. The main text still mentions “randomizing the order of scenarios and complexity levels.” Please retain a single, coherent formulation consistent with a between-subjects protocol.

2. Mutual exclusivity of conditions G1–G3—correct descriptions and figure captions.
   The responses declare exclusivity (G1: image+arrow+text; G2: audio+text, no arrows; G3: arrow+text). In the G2 description, however, “an arrow displays…” remains, and the caption to Fig. 9 indicates an arrow. Please remove these mentions for G2 or explicitly state that this was a descriptive error (with no impact on the data).

3. Units in Table 1—a minor inconsistency.
   In row T1, “30, 60, 80 m/s equivalent” remains. Please correct to “km/h (m/s)” in line with the description of speed zones.

4. Questionnaires—clarify denominators and presentation.
   In Fig. 11/Table 3, percentages are presented “for each group,” but values suggest a denominator other than n≈15 (e.g., 8.4%). It suffices to specify in the legend the n used for percentage calculations and to report both n and % in parallel (rounded to one decimal place). This is purely a presentation clarification.

5. Statistics—cosmetic reporting adjustments.
   For time, F(2,43)=65.34 is reported with p=0.004; for such an F, “p<.001” is appropriate. Please also add effect sizes (η²) and 95% CIs as reporting complements (without altering conclusions).

6. Composite index (errors + time)—brief completion.
   The text describes its construction, but no table/sentence reports the results. Please add one line (means, SDs, ANOVA + η²) and, optionally, a concise figure in the supplementary materials.

7. Minor editorial issues.
   Standardize table/figure numbering and complete any incomplete bibliography entries (visible empty items).

Strengths

• Operationalization of errors (thresholds for speeding, collisions, wrong-way driving) enhances replicability.

• Consistent quantitative results: G1 shows the fewest errors and the shortest times; values are coherent across abstract, results, and tables.

• The “Future work” section realistically identifies generalization avenues and next steps (traffic, night scenarios, objective cognitive-load measures).

Conclusion

The study offers a clear applied and empirical contribution. Following the indicated minor textual and editorial clarifications (with no changes to data or analyses), the manuscript will be ready for acceptance.

Comments on the Quality of English Language

The manuscript is readable but would benefit from moderate copy-editing to improve clarity and consistency. Please standardize verb tenses (past for Methods/Results), terminology and condition names, and units (km/h with m/s equivalents). Tighten long sentences, align figure/table captions with the text, and ensure consistent spelling and complete references. A light professional edit should be sufficient.

Author Response

Dear Reviewer/Editor, please find the attached file for answers/changes.

Author Response File: Author Response.pdf

This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This paper investigates image-arrow aids in a virtual reality driving simulator (VRDS) that enables trainees (new driver) to interpret instructions according to the correct course of 
action during performing their driving task.  I have some comments.

1. The advantages of image-arrow aids are not explicitly explained by theories.
2. The effectiveness of assistive tools in other studies (such as the HUD visual prompts in Reference [3]) should be further compared.
3. The sample size is too small
4. The experiment is limited to urban road scenarios and does not involve complex environments such as highways or nighttime driving.
5. As the intention of this paper is to track drivers. I think long-term effect shoud be evaluated.
6. Pleas cite more recent (2024-2025) advancements in the field of VR driving simulators to enhance the timeliness of the research.

Reviewer 2 Report

Comments and Suggestions for Authors

• Novelty and positioning: The introduction does not clearly demonstrate how the image-arrow aid differs from or advances beyond previously cited HUD and icon-based cue studies; the gap remains implicit.
• Experimental design clarity: A “balanced Latin-square order” is referenced, yet the study reads as a between-subjects comparison. Details on randomisation and participant demographics (gender, driving / gaming experience) are absent, leaving group equivalence uncertain.
• Methodological detail: The driving route length, manoeuvre count, speed zones, and task checklist are unspecified. The four-item questionnaire lacks provenance or validation evidence, and no baseline driving assessment is reported.
• Outcome alignment: Cognitive-load reduction is framed as a goal, but no direct cognitive-load or usability metric appears in the data set.

• Statistical support: Only means ± SD are provided. No inferential tests, effect sizes, or confidence intervals accompany claims of “significant” differences.

• The discussion and conclusion extrapolate benefits (e.g., reduced cognitive load, “most optimal” aid) without empirical backing and omit a limitations paragraph.

Comments on the Quality of English Language

Streamline long sentences, replace colloquialisms, and standardize tense usage. These revisions will greatly improve readability and credibility.