Abstract:
Background: Effectiveness of non-infrastructural visibility aids on bicycle crash
injury prevention was not well established, yet they were widely used.
Objective: To determine influence(s) of non-infrastructural visibility aids on
specified riders’ crashes and injuries within defined low visibility periods of the 24
hour day.
Setting: Eldoret Municipality, Kenya.
Study Design: Cross-sectional survey.
Methods: A pre tested semi structured, interviewer administered questionnaire was
used on 364 riders, to determine their self reported characteristics and crash injury
details for the year 2008. Non infrastructural visibility aids on riders and their bicycles
were determined by an observation checklist. Data entry, cleaning and analysis
employed the Computer program, Epi_Info version 3.5.1. Frequencies of variables
were determined. Two by two tables and multivariate logistic regression, determined
significant relations between specific non infrastructural visibility aids and riders’
crashes or injuries, specified by both defined crash periods (night, non-daytime or
whole day) and received management (self care, outpatient care or in-patient care).
Outputs were: Odds ratios, 95% confidence intervals, coefficients and p-values.
Presentations were in summary measures and tables.
Results: Riders’ main characteristics: 100% (N=364) male, 70.9 % (N=258) age
group 21-30 years, 80.8% (N=294) 4 years or less riding experience, 75.0% (N=273)
rode at least once at night, 99.2% (N=361) spoke Swahili and 90.4% (N=329) owned
the observed bicycle boda boda.
Proportions of bicycle boda boda with specific visibility aids: 62.9% (N=229) rear
reflectors and 27.2% (N=99) working headlight.
Riders’ proportions with reflective strips and group uniform were 55.5% (N=202) and
69.2% (N=252) respectively.
Riders’ injuries were 77.7% (N=369). Self involved riders’ injuries were the most
common, 54.2% (N=200), followed by motor vehicle related ones, 27.9% (N=103).
Among injuries managed by in-patient care, 60.0% (N=18) occurred within nondaytime
hours. Bright garments were associated with 34% reduction of non-daytime
crashes (OR=0.6577, 95%CI: 0.4539-0.9530).
At multivariate level, working headlight was associated with 75% reduction
(OR=0.2539, 95%CI: 0.0771-0.8358) of non-daytime injuries which were managed
by outpatient care.
Conclusion: Non-infrastructural visibility aids may be useful in
prevention of injuries within periods of the 24 hour day with low average natural
visibility.
