More than 500 New York City residents are injured badly enough to be treated in hospitals after being struck by bicyclists each year, according to an analysis by Hunter College professors. The number, while small compared with the number of pedestrians injured by cars, is a much higher figure than an earlier study by the same researchers found.

The professors surveyed hospital data gathered by the State Department of Health between 2007 and 2010 and found that roughly 1,000 pedestrians in New York State were seen at hospitals each year after being hit by cyclists, and that 55 percent of the accident victims were in New York City.

A 2009 analysis of different data by the professors, Peter Tuckel and William Milczarski, found that only a few more than 1,000 pedestrians were treated annually in hospitals in the whole country for injuries in collisions with cyclists.

Dr. Tuckel, a sociology professor, said these figures represent “the tip of the proverbial iceberg” because they only include pedestrians who wound up in the hospital. They do not include victims who visited their doctor’s office or a walk-in clinic for treatment.

Dr. Tuckel said that the new study (see also below) was prompted by questions from Nancy Gruskin, the founder of an organization that encourages safe cycling. Ms. Gruskin founded the Stuart Gruskin Family Foundation after her husband was fatally injured by a delivery man on a bike on 42nd Street in 2009. The latest study was done independently by Hunter, however, and the Gruskin foundation did not pay for the research, Dr. Tuckel said.

Statistics on bicycling accidents have not been kept by the city in the past, but a new law mandating reporting and tabulating bicycle accidents will go into effect Oct. 1.

The state hospital data analyzed in the new report lists the borough or county of residence of the accident victims, not of the location of the accident itself.

But Dr. Tuckel noted that within the city, the ranking of accidents by residence of victim — Brooklyn, followed by Manhattan, Queens, the Bronx and Staten Island — paralleled the overall rankings for locations of pedestrian deaths in all accidents in New York City. This, he said — in addition to common sense — implied a strong correlation between the residence of the victim and the borough or county in which the accident occurred.

About 33 percent of the accident victims who live in New York City lived in Brooklyn, and an additional 28 percent lived in Manhattan. The ZIP code with the most residents hit by cyclists was 10029, East Harlem.

Seth Solomonow, a spokesman for the city’s Department of Transportation, said in a statement: “There are nearly 10,000 people who visit the hospital citywide each year after being struck by cars, so this is actually a pretty low number — one that’s been kept low because of our safety investments. We still have to drive it down further and will continue to work with N.Y.P.D. to enforce the law for everyone on the road and install bike lanes to separate vehicles from cyclists and cyclists from pedestrians. These make streets safer for everyone who uses them and have helped make the last four years the safest in the city in a century.”

The release of the report follows last week’s selection of an operator for the city’s bike share program next year. Michael Murphy, a spokesman for the bike advocacy group Transportation Alternatives, encouraged New Yorkers to note that these accidents declined slightly over the past four years statewide. The Hunter analysis found 927 bicycle accidents followed by hospital treatment for pedestrians statewide in 2010, down 15 percent from 1,097 in 2007.

Mr. Murphy also encouraged cycling’s fans and critics to keep these numbers in perspective.

“Motor vehicles are responsible for over 70,000 injuries every year in New York City, and hundreds of annual deaths,” Mr. Murphy said. “We can ignore that number and bash bikes, or we can get serious about safety and work to stop all traffic casualties.”

Ms. Gruskin said that she supported the new bike share program. But she added, “It must be safe cycling. There doesn’t seem to be people asking safety questions.”



