By Jonathan Purtle

Textbooks will tell you that statistics are the basis for most public health decisions. In reality, it's evocative displays of remembrance, solidarity, and outrage about lives lost that really get things done.

Wednesday's Ride of Silence is one such powerful display.

The Ride of Silence is an annual bike ride — many annual bike rides, actually, — that commemorates the lives of bicyclists who have been killed or injured on public roads. Motorists who see, hear or read about it can't help becoming more aware of the threats that they pose to cyclists.

The Philadelphia ride will begin at 6:45 PM Wednesday in front of the Art Museum steps. It will be in memory of seven cyclists who were killed in 2011-2012 around the Delaware Valley; the locations have all been mapped. One was Gregory Loper, a city resident and father of 11 who was killed by a drunk driver in the 1900 block of East Lehigh Avenue in November. Participants will ride in silence as they make the somber, eight mile trip, escorted by police.

There are local Pennsylvania rides in Doylestown, Trappe, West Chester and elsewhere; and at the Shore, among other places in New Jersey.

The first Ride of Silence was on the streets of Dallas in 2003, after a cyclist named Larry Schwartz was killed by a school bus mirror while riding. A friend of his named Chris Phelan organized the initial ride. Word of its emotive power spread quickly, and today hundreds of Rides of Silence take place around world on the third Wednesday in May. An estimated 12,033 cyclists participated last year.

Bicycle enthusiasts Raymond Scheinfeld and John Siemiarowski organized the first Philadelphia ride in 2005, getting support from the Bicycle Coalition of Greater Philadelphia and the Philadelphia Police Department. "We long for the day that we can stand up and say that there were no deaths in the Delaware Valley this year," said Scheinfeld, "but unfortunately this has yet to happen."

According to statistics from the National Highway Traffic Safety Administration, 630 bicyclists were killed on U.S. roads in 2009, including 13 in New Jersey and 15 in Pennsylvania. Most of the deaths nationally were in urban areas (70 percent) and at non-intersection locations (67 percent). The largest proportion was between the hours of 4 and 8 p.m. (27 percent). In fully one third of the fatal accidents, either the cyclist or the motorist had a blood alcohol concentration of .08 or higher.

The risks of cycling are relatively small, but quite serious — something that city officials should keep in mind as biking continues to grow.

A recent report by the Bicycle Coalition of Greater Philadelphia highlights the increasing preference for getting around on two wheels. In 2009, the most recent year for which data are available, Philadelphia ranked No. 1 in bike commuting among the nation's 10 largest cities. More than 2.1 percent of Philadelphians reported bicycling as their primary mode of transportation to work (that would include both bloggers at The Public's Health and, on occasion, our editor). Chicago came in a not-so-close second at 1.1 percent. Bicycle commuting in Philadelphia increased 151 percent between 2000 and 2009.

I hope you can join me and other bicycle advocates Wednesday evening. The Ride of Silence is free of charge and takes about two hours . Helmets are mandatory and lights are highly recommended. But you'll have to save conversation for another time.

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