Trip weather type Clear sky Cloud cover Fog, mist, rain or snow Wind Age 19 - 29 30 - 39 40 - 49 50 - 59 ≥ 60 Yes/No 172/305 44/88 10/50 4/10 78/185 54/114 41/76 37/46 19/37 Teschke et al. BMC Public Health 2012, 12:765 http://www.biomedcentral.com/1471-2458/12/765 Page 5 of 9 Table 4 Associations between whether highly visible clothing was worn on the torso and trip or personal characteristics, variables retained in adjusted analysis only, each variable on its own (unadjusted) and in multiple logistic regression (adjusted) Highly visible clothing worn on the torso (% Yes/% No)* Unadjusted Odds Ratio Adjusted Odds Ratio (95% Confidence Interval) (95% Confidence Interval) (36/64) (33/67) (16/84) (29/71) (30/70) (32/68) (35/65) (45/55) (34/66) 1 (reference) 0.88 (0.53 – 1.33) 0.36 (0.18 – 0.72) 0.79 (0.24 – 2.60) 1 (reference) 1.15 (0.75 – 1.74) 1.32 (0.83 – 2.10) 1.95 (1.17 – 3.25) 1.25 (0.68 – 2.32) 1.17 (1.05 - 1.36) 1 (reference) 0.85 (0.56 – 1.29) 0.33 (0.16 – 0.68) 0.85 (0.26 – 2.86) 1 (reference) 1.19 (0.78 – 1.83) 1.35 (0.84 – 2.16) 1.85 (1.10 – 3.10) 1.27 (0.68 – 2.38) 1.17 (1.05 - 1.30) Cycling frequency (trips per year)† 164 vs. 145 Significant associations in bold. * Row percent. † = continuous variable: mean trips per year for yes vs. no; odds ratio and 95% confidence interval for 52 trips per year (equivalent to cycling once per week). in various Canadian cities and, to date, all have bikes equipped with front and rear LED lights that are on whenever the bicycle is moving. Bike share systems were not in place in Toronto or Vancouver at the time of our study. Use of conspicuous colours (white, yellow, orange or red) on the torso (33%) was more common than use of lights in daytime, however the majority of participants wore other colours. Poor weather was associated with less use of conspicuous clothing, opposite to what would be desirable, perhaps indicative of the typical colours of coats sold for cold or rainy weather. It is possible that some of the dark or muted coloured coats had reflective tape that would be visible when illuminated at night, but we did not document this in a systematic way. Brightly coloured jackets are sold in bicycle shops, and these may be more often purchased by frequent cyclists; they were more likely to wear conspicuous clothing in this study. Of the three types of safety equipment examined here, helmets have been the most frequently studied. Studies that elicited self-reported regular use of helmets in Oregon and New Zealand indicated very high propor- tions (95% or more) [19,21], but these levels seem un- realistically high compared to observations of cyclists in the field and self-reports about a specific trip (e.g., an in- jury trip, as in this study). In US and Canadian jurisdic- tions, typical proportions of adults wearing helmets have been in the range of 30 to 50% where there is no legal requirement to do so [10-12,15,16,18,22,23,25], and somewhat over 70% where legislation requires use by adults [16]. These proportions are comparable to (though slightly lower than) our findings, perhaps be- cause our sample was skewed to regular cyclists. In con- tinental Europe, helmet use rates are considerably lower, with reports of 2% in Paris [15], 12% in Germany [14], and 2-6% among pediatricians in the Netherlands [24]. A UK study reported 27% of observed cyclists wore hel- mets [20]. Factors associated with not wearing a helmet are similar to many of those found in our study: alcohol use [10-12]; younger ages [14,16,25]; lower education and income [14,16]; and less distance or duration of cyc- ling [14,15,25]. Studies examining sex have not found consistent relationships [14-16,22], though in North America (as in our study) women appear to be more likely to use helmets [15,16]. Studies of the prevalence of light use have mainly fo- cused on use at dawn, dusk and night, rather than dur- ing the day. Several have surveyed self-reported regular use and may suffer from over-reporting: 92% indicated back light and 87% front light use in New Zealand [21]; 90% back light and 83% front light use in Australia [13]; 96% any light use in Portland, Oregon [19]. Those doing direct field observations have found lower proportions: 50% rear light use, 48% front light use in the UK [20]; 40 to 60% use at night in New Zealand [17]. One study compared Paris and Boston and found that 47% of cyclists used lights at night in Paris versus 15% in Boston [15]. Factors associated with light use were rarely stud- ied, but included results similar to ours: light use was more common among those who wore helmets [20]; and among men, older adults, and on weekdays [15].