Assessing the potential for bias in direct observation of adult commuter cycling and helmet use

Kraemer, John; Zaccaro, Heather; Roffenbender, Jason S.; Baig, Sabeeh A; Graves, Megan E; Hauler, Katherine J; Hussain, Aamir; Mulroy, Faith E

doi:10.1136/injuryprev-2014-041285

Cited by 14 publications

(7 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Thus, a more flexible ticket type such as a reduced contingent ticket or a flat-rate ticket that is only valid in bad weather could be attractive. This option could be seasonal, such as in winter months, or even daily, if bad weather is forecasted, which has been shown to reduce cyclist levels (Kraemer et al, 2015;Wessel, 2020). If such flexible tickets were not available, more transport mode switchers would resort to the car during bad weather, thus exacerbating environmental problems.…”

Section: Comparison Of Bicycle Indicesmentioning

confidence: 99%

Some people feel the rain, others just get wet: An analysis of regional differences in the effects of weather on cycling

Goldmann

Wessel

2021

Research in Transportation Business & Management

View full text Add to dashboard Cite

Between cities and regions, not only cycling levels differ, but also the reactions of cyclists to adverse weather conditions. Using data from 122 automated bicycle counting stations in 30 German cities, and a composite index of adverse weather conditions that consists of air temperature, precipitation, wind speed, relative humidity, and cloud coverage, we calculate city-specific weather elasticities of the level of utilitarian cycling. The results show that these weather elasticities vary significantly between cities. Our next step is to analyze various determinants of weather elasticities, which reveals that the share of young inhabitants and the density of the cycle network have a positive impact on weather resilience. Based on the notion that resilience to adverse weather conditions reflects a revealed part of a city's bicycle culture, the weather elasticities can be used to create a ranking of bicycle cities. This ranking is positively correlated with a ranking based on the modal share of cycling, as well as with other rankings based on stated preference surveys or external conditions such as infrastructure or cycling safety. JEL: R49.

show abstract

Section: Comparison Of Bicycle Indicesmentioning

confidence: 99%

Some people feel the rain, others just get wet: An analysis of regional differences in the effects of weather on cycling

Goldmann

Wessel

2021

Research in Transportation Business & Management

View full text Add to dashboard Cite

show abstract

“…Age [24,35], race/ethnicity [4,5,35], and sex [4,24,35] have previously been found to correlate with helmet use and potentially varied between intervention and control populations, so they were included as control variables. Age was categorized as 14 years and younger, single years from 15 to 17, and as 18 and older.…”

Section: Causal Identificationmentioning

confidence: 99%

“…Direct cyclist observation is the primary alternative and likely has less error in helmet ascertainment but greater error estimating age and demographic variables [40]. Factors related to observation periods can also bias observed helmet use [35]. Triangulating results through both survey and observation-based studies is valuable.…”

Section: Limitationsmentioning

confidence: 99%

Helmet Laws, Helmet Use, and Bicycle Ridership

Kraemer

2016

Journal of Adolescent Health

View full text Add to dashboard Cite

show abstract

“…While helmet use can be reliably measured via other techniques, such as direct observation, ascertaining and assigning race and ethnicity by observation raises both normative and measurement issues (Smith 2001; Kraemer et al 2012; Kraemer et al 2015). While self-reported race and ethnicity is still subject to recording mistakes, it avoids external assignment and thus is more likely to represent the social constructs to which race and ethnicity relate and which affect helmet use.…”

Section: Discussionmentioning

confidence: 99%

Bicycle helmet laws and persistent racial and ethnic helmet use disparities among urban high school students: a repeated cross-sectional analysis

Kraemer

2016

Inj. Epidemiol.

View full text Add to dashboard Cite

BackgroundBicycle helmet laws generally increase helmet usage, but few studies assess whether helmet laws reduce disparities. The objective of this study is to assess changes in racial/ethnic disparities in helmet use among high school students in urban jurisdictions where laws were previously determined to increase overall helmet use.MethodsLog-binomial models were fit to four districts’ 1991–2013 Youth Risk Behavior Survey (YRBS) data. Post-regression predictive margins were used to calculate adjusted bicycle helmet use proportions, assess before-to-after changes in race/ethnicity specific helmet use, and estimate changes in disparities from jurisdictions’ white subpopulations.ResultsHelmet use among white students increased by 10.2 percentage points in two Florida counties (p < 0.001), 20.1 points in Dallas (p < 0.001), and 24.4 points in San Diego (p < 0.001). Increases among African Americans were 6.1 percentage points in the Florida counties (p < 0.001), 8.2 points in Dallas (p < 0.001), and 6.3 points in San Diego (p = 0.070). Use increased among Latino students in the Florida counties (4.3 percentage points, p = 0.016) and Dallas (6.2, p = 0.002), but not significantly in San Diego. San Diego helmet use among Asian students increased by 12.8 percentage points (p < 0.001). Because helmet use increased more for white students, helmet laws were associated with increased disparities. In the Florida counties, disparities increased significantly by 5.9 percentage points for Latino students (p = 0.045). San Diego disparities worsened by 18.1 (p < 0.001), 21.3 (p < 0.001), and 11.6 (p = 0.013) percentage points among African American, Latino, and Asian students respectively. Dallas disparities increased by 11.9 (p = 0.015) and 14.0 (p = 0.003) percentage points among African American and Latino students. Increased disparities generally persisted for follow-up time of at least a decade. Main study limitations include the possibility of helmet use reporting error and limited socioeconomic variables in YRBS datasets.ConclusionsHelmet use increased across racial/ethnic subpopulations, but greater increases among white students increased disparities. Policymakers should couple laws with other approaches to reduce helmet disparities and cycling injuries.Electronic supplementary materialThe online version of this article (doi:10.1186/s40621-016-0086-3) contains supplementary material, which is available to authorized users.

show abstract

Assessing the potential for bias in direct observation of adult commuter cycling and helmet use

Abstract: Objectives Bicycling and helmet surveillance, research, and programme evaluation depend on accurate measurement by direct observation, but it is unclear whether weather and other exogenous factors introduce bias into observed counts of cyclists and helmet use.

Cited by 14 publications

References 24 publications

Some people feel the rain, others just get wet: An analysis of regional differences in the effects of weather on cycling

Some people feel the rain, others just get wet: An analysis of regional differences in the effects of weather on cycling

Helmet Laws, Helmet Use, and Bicycle Ridership

Bicycle helmet laws and persistent racial and ethnic helmet use disparities among urban high school students: a repeated cross-sectional analysis

Contact Info

Product

Resources

About