How has the Covid-19 pandemic affected wheelchair users? Time-series analysis of the number of railway passengers in Tokyo

The COVID-19 pandemic significantly impacted public transportation globally. Lockdowns, social distancing measures, and fear of infection led to a marked decrease in public transport usage, with a modal shift towards private transport. This reduction in public transport usage raised concerns about its potential negative impact on vulnerable populations, including people with disabilities (PwDs). PwDs already faced many barriers to public transport, and the pandemic exacerbated these challenges, creating "new barriers" to their social participation. While qualitative studies have documented the difficulties faced by PwDs during the pandemic, quantitative data on the extent of this impact remains limited. This study addresses this gap by focusing on wheelchair users in Tokyo, a city with a significant reliance on rail transport (approximately 30%). The research question is: How has the COVID-19 pandemic affected the number of wheelchair users accessing railway services in Tokyo? The study uses time-series data to analyze daily average rail passenger numbers at nine selected Tokyo stations, carefully controlling for pre-existing seasonal variations to isolate the impact of the pandemic.

The study reviews existing literature based on four criteria: (a) research on PwDs during COVID-19; (b) comparative research on people with and without disabilities; (c) analysis of transportation during COVID-19; and (d) time-series analysis during COVID-19. Several studies examined the impact of COVID-19 on PwDs, often using qualitative methods such as literature reviews, questionnaires, and interviews. These studies highlighted increased difficulties in accessing healthcare, reduced social participation, and heightened concerns about infection control in public spaces. However, quantitative evidence comparing the impact on PwDs versus the general population regarding transport use was lacking. Studies analyzing transport usage during the pandemic often focused on overall ridership declines without specific consideration of PwDs or using aggregate data. Some studies employed time-series analysis of general transport usage, but these didn't focus on PwDs. The current study addresses this gap by incorporating all four criteria, providing a quantitative and comparative analysis of the impact of the pandemic on wheelchair users specifically.

The study analyzed daily average rail passenger data from April 2012 to December 2021 at nine Tokyo train stations. These stations were selected to minimize confounding factors such as new barrier-free facilities. Data included the number of wheelchair passengers (based on ramp board usage records by station staff) and the total number of passengers. A state-space model was used to analyze the time-series data. This model allows for the decomposition of the time series into trend, seasonal, stationary autoregressive (AR) components, and noise. The pre-COVID-19 period was modeled separately from the post-COVID-19 period. The seasonal components identified in the pre-pandemic model were removed from the data to isolate the impact of COVID-19. Akaike's Information Criterion (AIC) was used to determine the optimal model order. Change points in the time series were identified using a locally stationary AR model, indicating when the time series' structure changed significantly. A difference-in-differences analysis compared changes in wheelchair passenger numbers to changes in total passenger numbers before and after the pandemic. A pre-COVID-19 model was also used to generate counterfactual predictions of what passenger numbers might have been without the pandemic. The difference between these predictions and the actual observed data represents the estimated impact of COVID-19.

The analysis revealed two key findings. First, the change point for the decline in passenger numbers was identified as March 2020, preceding the official declaration of the state of emergency. This suggests that fear and precautionary measures, rather than official restrictions, primarily drove the initial decline. Second, a significant difference was found between the impact on wheelchair users and all passengers. The difference-in-differences analysis showed that, while total rail passenger numbers decreased by 20 percentage points from 2019 to 2021, wheelchair passenger numbers declined by 46 percentage points, indicating a considerably greater impact on this vulnerable group. The time-series model further showed that while total passenger numbers declined by an average of 21 percentage points during the pandemic period (January 2020 - December 2021), wheelchair passenger numbers declined by an average of 44 percentage points. This translates to a 23 percentage point greater reduction for wheelchair users. The most significant decline in both categories occurred in May 2020, although the impact on wheelchair users was far more substantial. Even by December 2021, the recovery was less significant for wheelchair users, indicating a lasting impact of the pandemic.

The findings confirm that the COVID-19 pandemic disproportionately affected wheelchair users' access to public transportation in Tokyo. The early decline in passenger numbers, preceding official restrictions, highlights the role of public fear and self-imposed social distancing in shaping travel behavior. The significantly larger reduction in wheelchair passenger numbers compared to all passengers strongly suggests that pre-existing barriers to public transport access were exacerbated by the pandemic and the implemented measures. The data suggest that factors beyond general economic slowdown or teleworking contributed to the decrease in wheelchair users, likely due to stricter infection control measures in healthcare and social care settings, impacting their mobility and opportunities for social participation. This study provides quantitative support to previous qualitative research indicating that the pandemic resulted in a reduction in social participation for individuals with disabilities.

This study provides quantitative evidence of the disproportionate impact of the COVID-19 pandemic on wheelchair users' access to public transportation in Tokyo. The findings highlight the need for inclusive planning and mitigation strategies to address the unique challenges faced by PwDs during public health emergencies. Future research could explore the socio-economic factors that influence the differential impact on wheelchair users compared to the general population and examine the long-term consequences of the pandemic on their mobility and participation in society. Further research could also involve expanding the study to encompass a broader range of disabilities and transportation modes.

This study has two main limitations. First, the data is specific to wheelchair users utilizing rail transport in Tokyo, and results may not be generalizable to other contexts or disability types. Second, the analysis relies on data collected by rail operators and does not include socioeconomic information about passengers. Therefore, conclusions about the underlying causes of the observed disparities are made in relation to existing research and can be considered indirect rather than causally inferred.