Assessing Roundabout Safety Perceptions under Heterogeneous Traffic: Socio-Demographic and Geometric Influences in Indian Urban Contexts
Pith reviewed 2026-05-18 13:00 UTC · model grok-4.3
The pith
Surveys of 1,530 Indian roundabout users show single-lane designs are viewed as safer for entry and circulation by middle-aged drivers while multi-lane versions raise exit risks for younger and less experienced users.
A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.
Core claim
Single-lane roundabouts were perceived as safer during entry and circulation, with a significant prominence among middle-aged users. In contrast, double- and multi-lane roundabouts presented higher perceived risks during exit maneuvers, especially among young, inexperienced, unemployed or self-employed users. The merging area was seen as the most dangerous spot overall, while vulnerable road users reported significantly higher perceived risks under suboptimal lighting conditions.
What carries the argument
Questionnaire responses from 1,530 users analyzed via multiple correspondence analysis, cluster analysis, factor analysis, and multinomial logistic regression to relate socio-demographic traits and geometric features to perceived safety at entry, circulation, and exit.
If this is right
- Safety upgrades should prioritize exit geometry and signage at double- and multi-lane roundabouts for young and inexperienced drivers.
- Lighting improvements at roundabouts would address elevated risks reported by vulnerable road users.
- Single-lane designs may be preferred where middle-aged and experienced car users predominate to lower overall perceived risk.
- Merging areas require attention in all roundabout types since they were identified as the most dangerous location.
Where Pith is reading between the lines
- The same perception patterns may not hold in cities with more homogeneous traffic or different enforcement levels, suggesting comparative studies across traffic regimes.
- Pairing these perception findings with actual crash statistics at the studied sites could test whether self-reports predict real safety outcomes.
- Targeted driver training for young users on multi-lane exits might shift risk perceptions and reduce incidents if the link between perception and behavior is strong.
Load-bearing premise
Self-reported safety perceptions from the questionnaires accurately reflect genuine risk concerns and the 1,530 respondents represent typical roundabout users in the two cities without major selection or reporting biases.
What would settle it
If objective crash or near-miss counts from the same roundabouts show no difference in incidents by lane count for middle-aged versus young users or no elevation in exit incidents at multi-lane sites, the perception-based claims would be contradicted.
read the original abstract
Evaluation of the safety perceptions of roundabout users is crucial for improving road safety in mixed-traffic environments. The crash- and conflict-based analyses do not incorporate the socio-demographic characteristics of the roundabout users, which can only be captured through questionnaire surveys on a larger scale. This research evaluated the relationship of roundabout safety perception with demographic factors, driving characteristics, and varying roundabout geometries using multiple correspondence analysis, cluster analysis, factor analysis, and multinomial logistic regression. The study analyzed data from 1,530 respondents across two Indian cities. The study identified three roundabout user clusters. Single-lane roundabouts were perceived as safer during entry and circulation, with a significant prominence among middle-aged users. In contrast, double- and multi-lane roundabouts presented higher perceived risks during exit maneuvers, especially among young, inexperienced, unemployed/self-employed users. Vulnerable road users reported significantly higher perceived risks, especially under suboptimal lighting conditions. Respondents with 10-20 years of driving experience, especially car users, perceived lower risk at single-lane roundabouts but acknowledged the higher risk linked to speed variations and complex maneuvers at multi-lane roundabouts. Driving experience, vehicle type, and geometric configurations were crucial in roundabout safety perception. The study highlighted the need to improve the built environment of roundabouts for vulnerable road users. The roundabout merging area was perceived as the most dangerous spot; however, exits were also perceived as dangerous for double- and multi-lane roundabouts. The findings can benefit policymakers, engineers, and urban planners by enabling them to deploy targeted safety interventions based on issues highlighted in the study.
Editorial analysis
A structured set of objections, weighed in public.
Referee Report
Summary. The paper analyzes survey responses from 1,530 roundabout users in two Indian cities to examine how socio-demographic factors, driving characteristics, and geometric features (single-, double-, and multi-lane) influence perceived safety. Using multiple correspondence analysis, cluster analysis, factor analysis, and multinomial logistic regression, it identifies three user clusters and reports that single-lane roundabouts are perceived as safer during entry and circulation (especially by middle-aged users), while double- and multi-lane roundabouts carry higher perceived exit risks (particularly for young, inexperienced, unemployed/self-employed users). Vulnerable road users report elevated risks under poor lighting; the merging area is flagged as most dangerous overall, with exits also problematic for multi-lane designs. The study concludes that driving experience, vehicle type, and geometry are key determinants and calls for targeted built-environment improvements.
Significance. If the survey data validly capture population-level perceptions, the work supplies actionable, user-segmented evidence for safety interventions in heterogeneous Indian traffic that crash- or conflict-based studies alone cannot provide. The multi-method approach and sample size are strengths; the emphasis on vulnerable users and specific geometric phases offers clear policy relevance for planners and engineers.
major comments (2)
- [Methods / Data collection] Data collection / Methods: The manuscript provides no sampling frame, response rate, or explicit steps taken to address selection bias or non-response in the 1,530-respondent survey across the two cities. Because the central claims rest entirely on the representativeness of self-reported perceptions, this omission is load-bearing; without these details it is impossible to evaluate whether the reported differences by age, experience, and lane configuration generalize beyond the sampled respondents.
- [Results / Regression analysis] Results / Multinomial logistic regression: The paper does not report model diagnostics (e.g., goodness-of-fit, multicollinearity checks, or proportional-odds tests if ordinal elements are present) or effect-size measures alongside the significance statements for the geometric and socio-demographic predictors. This weakens the ability to judge the practical magnitude of the claimed differences between single-lane and multi-lane roundabouts.
minor comments (3)
- [Abstract / Introduction] Abstract and introduction: The abstract states that “crash- and conflict-based analyses do not incorporate socio-demographic characteristics,” but does not cite any specific prior Indian roundabout studies that were limited in this way; adding 1–2 targeted references would strengthen the motivation.
- [Introduction] Terminology: “Heterogeneous traffic” is used throughout but never operationally defined (e.g., mix of motorized two-wheelers, cars, and non-motorized users); a brief operational definition or reference to standard Indian traffic-composition metrics would improve clarity.
- [Results / Figures] Figure and table captions: Several figures showing cluster profiles or factor loadings lack axis labels or legends that explicitly link back to the variable categories used in the MCA; this reduces immediate interpretability.
Simulated Author's Rebuttal
We thank the referee for their thoughtful review and constructive suggestions. We have carefully considered the comments on data collection and regression analysis. Our point-by-point responses are provided below, and we will revise the manuscript accordingly where possible.
read point-by-point responses
-
Referee: [Methods / Data collection] Data collection / Methods: The manuscript provides no sampling frame, response rate, or explicit steps taken to address selection bias or non-response in the 1,530-respondent survey across the two cities. Because the central claims rest entirely on the representativeness of self-reported perceptions, this omission is load-bearing; without these details it is impossible to evaluate whether the reported differences by age, experience, and lane configuration generalize beyond the sampled respondents.
Authors: We appreciate the referee pointing out this critical detail. The survey employed an intercept sampling method at selected roundabouts in the two cities, with data collected during various times of the day to capture a diverse user base. Participation was voluntary, and efforts were made to include users from different socio-demographic backgrounds. However, as is common in field surveys of this nature, a formal sampling frame was not used, and response rates were not systematically recorded due to the dynamic nature of the locations. We acknowledge this as a limitation regarding generalizability. In the revised manuscript, we will expand the Methods section to describe the data collection process in greater detail, including the specific roundabouts surveyed, time periods, and any measures taken to reduce selection bias, such as varying collection times and locations. revision: partial
-
Referee: [Results / Regression analysis] Results / Multinomial logistic regression: The paper does not report model diagnostics (e.g., goodness-of-fit, multicollinearity checks, or proportional-odds tests if ordinal elements are present) or effect-size measures alongside the significance statements for the geometric and socio-demographic predictors. This weakens the ability to judge the practical magnitude of the claimed differences between single-lane and multi-lane roundabouts.
Authors: We agree that including model diagnostics and effect sizes would improve the robustness of our findings. The analysis used multinomial logistic regression with categorical outcomes for perceived safety. We will add the following in the revised manuscript: (1) likelihood ratio tests and pseudo R-squared values for model fit; (2) variance inflation factor (VIF) values to check for multicollinearity among predictors; and (3) odds ratios with confidence intervals as effect size measures. Since the model is multinomial rather than ordinal, proportional odds tests do not apply. These additions will allow readers to better assess the practical significance of the geometric and socio-demographic influences. revision: yes
- The precise response rate and number of non-respondents, as these were not documented during the on-site intercept survey.
Circularity Check
No circularity: findings derive directly from primary survey data and standard statistical processing
full rationale
The paper collects primary questionnaire responses from 1,530 users and applies off-the-shelf multivariate techniques (multiple correspondence analysis, cluster analysis, factor analysis, multinomial logistic regression) to relate safety perceptions to demographics, experience, and geometry. No equations, fitted parameters, or predictions are defined in terms of themselves; no uniqueness theorems or ansatzes are imported via self-citation; the central claims are statistical summaries of the observed response patterns rather than reductions to prior inputs. The derivation chain is therefore self-contained against the collected data.
Axiom & Free-Parameter Ledger
axioms (2)
- standard math Multinomial logistic regression assumptions including independence of irrelevant alternatives hold for the safety perception categories
- domain assumption Self-reported questionnaire responses provide unbiased measures of actual safety perceptions
Reference graph
Works this paper leans on
-
[1]
Available at: https://doi.org/10.62154/ajastr.2024.016.010357. Bie, J., Lo, H.K. and Wong, S.C. (2008) ‘Circulatory markings at double -lane traffic roundabout: Comparison of two marking schemes’, Journal of Transportation Engineering , 134(9), pp. 378 –388. Available at: https://doi.org/10.1061/(ASCE)0733-947X(2008)134:9(378). Borowsky, A. and Oron-Gilad...
-
[2]
Available at: https://doi.org/10.1016/j.aap.2011.02.023. Novák, J., Ambros, J. and Frič, J. (2018) ‘How Roundabout Entry Design Parameters Influence Safety’, Transportation Research Record , 2672(34), pp. 73 –84. Available at: https://doi.org/10.1177/0361198118776159. Oltedal, S. and Rundmo, T. (2 007) ‘Using cluster analysis to test the cultural theory o...
discussion (0)
Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.