Trip time of day Dawn or dusk Day Night Trip weather type Clear sky Cloud cover Fog, mist, rain or snow Wind Trip day of week Weekday Weekend Sex Male Female No Yes Helmet worn during trip Significant associations in bold. * Row percent. Yes/No 32/503 22/28 81/24 63/414 39/93 25/35 3/11 109/422 26/133 92/318 43/237 33/179 102/376 (6/94) (44/56) (77/23) (13/87) (30/70) (42/58) (21/79) (21/79) (16/84) (22/78) (15/85) (16/84) (21/79) 1 (reference) 12.6 (6.49 – 24.6) 50.2 (30.0 – 90.2) 1 (reference) 2.91 (1.83 – 4.61) 4.85 (2.72 – 8.65) 2.03 (0.55 – 7.61) 1 (reference) 0.73 (0.45 – 1.19) 1 (reference) 0.60 (0.40 – 0.91) 1 (reference) 1.45 (0.93 – 2.25) 1 (reference) 13.2 (6.42 – 27.2) 71.1 (35.8 – 141) 1 (reference) 3.43 (1.83 – 6.41) 3.07 (1.33 – 7.10) 1.75 (0.30 – 10.4) 1 (reference) 0.48 (0.24 – 0.97) 1 (reference) 0.56 (0.32 – 0.99) 1 (reference) 3.15 (1.61 – 6.16) Teschke et al. BMC Public Health 2012, 12:765 http://www.biomedcentral.com/1471-2458/12/765 Page 4 of 9 Table 3 Associations between whether at least one bike light was turned on and trip or personal characteristics, variables retained in adjusted analysis only, each variable on its own (unadjusted) and in multiple logistic regression (adjusted) At least one bike light turned on (% Yes/% No)* Unadjusted Odds Ratio (95% Confidence Interval) Adjusted Odds Ratio (95% Confidence Interval) also prompted light use, with strong associations for cloud cover, fog, mist, rain or snow. Those on weekend trips and women were less likely to use lights (even after adjusting for weather and time of day). Helmet use was positively associated with use of lights. Few variables showed associations with wearing highly visible clothing on the torso (Table 4). Cold, wet weather was associated with lower odds of wearing conspicuous clothing. Older adults (50 to 59 years) and those who were more frequent cyclists were more likely to wear such clothing. In a repeat of the analyses for highly vis- ible clothing, excluding the 56 participants who could not recall the colour of the clothing they wore, the vari- ables associated and their odds ratios and confidence intervals were nearly identical to the adjusted analyses reported in Table 4. An array of variables were associated with helmet use (Table 5). Participants in Toronto, where there is no legal requirement for adults to wear helmets, were less likely to wear them (59%) than those in Vancouver (76%). Trip characteristics positively associated with hel- met use included use of a bike light, longer trip dis- tances, and use of a hybrid style of bicycle. Cruiser bike use and consumption of alcohol in the 6 hours prior to the trip were associated with lower odds of helmet use. Personal characteristics positively associated with helmet use included female sex, older age, higher income and higher education. Discussion The most commonly used safety equipment was helmets (69% overall), even in Toronto where use of helmets is not required of adults. This reflects the emphasis on hel- mets as “the major safety measure for bicyclists” in Canada [27]. Use of lights was uncommon (~20%), but it is required at night in both jurisdictions, and these laws were followed by about the same proportion of cyclists as complied with helmet legislation in Vancouver (~77%). Use of lights at dusk and dawn is also mandated by legislation, but this was much less prevalent in our study. The use of lights in the daytime was rare. Since 1990, the Canadian Motor Vehicle Safety Standard has required that all motor vehicles be equipped with front daytime running lights, so it is interesting that the po- tential for increasing the visibility of cyclists via use of lights in daytime has not been recognized either in law or by individuals. A new development related to this issue is bike share systems. These are being implemented