randya

From the peer-reviewed literature; just published in the Environmental Health Journal by five researchers from the University of British Columbia:

Methods
We reviewed studies of the impact of transportation infrastructure on bicyclist safety. The results were tabulated within two categories of infrastructure, namely that at intersections (e.g. roundabouts, traffic lights) or between intersections on “straightaways” (e.g. bike lanes or paths). To assess safety, studies examining the following outcomes were included: injuries; injury severity; and crashes (collisions and/or falls).

Results
The literature to date on transportation infrastructure and cyclist safety is limited by the incomplete range of facilities studied and difficulties in controlling for exposure to risk. However, evidence from the 23 papers reviewed (eight that examined intersections and 15 that examined straightaways) suggests that infrastructure influences injury and crash risk. Intersection studies focused mainly on roundabouts. They found that multi-lane roundabouts can significantly increase risk to bicyclists unless a separated cycle track is included in the design. Studies of straightaways grouped facilities into few categories, such that facilities with potentially different risks may have been classified within a single category. Results to date suggest that sidewalks and multi-use trails pose the highest risk, major roads are more hazardous than minor roads, and the presence of bicycle facilities (e.g. on-road bike routes, on-road marked bike lanes, and off-road bike paths) was associated with the lowest risk.

Conclusions
Evidence is beginning to accumulate that purpose-built bicycle-specific facilities reduce crashes and injuries among cyclists, providing the basis for initial transportation engineering guidelines for cyclist safety. Street lighting, paved surfaces, and low-angled grades are additional factors that appear to improve cyclist safety. Future research examining a greater variety of infrastructure would allow development of more detailed guidelines.

More selected quotes:

Bicyclists are vulnerable because they must frequently share the same infrastructure with motorized vehicles, and yet bicycles offer their users no physical protection in the event of a crash. In addition, the mass of a typical automobile is at least an order of magnitude greater than a bicycle plus its rider, and motorized vehicles have top speeds that are considerably faster than bicycles. As a result, bicycle riders who are involved in a crash are exposed to a much higher risk of injury compared to motor vehicle users (with the exception of motorcycle riders).

In this paper we review the evidence on how different types of transportation infrastructure affect bicyclists’ safety. This paper is organized as follows: first we provide an overview of bicycling safety and ridership. Next we offer definitions of, and alternative terminology for, the transportation infrastructure used by cyclists that might be expected to influence their safety (Table 1). We describe our literature search methodology and the inclusion and exclusion criteria, and present the results of the search in two detailed tables. Table 2 describes studies that assess the safety of intersections for cyclists, and Table 3 describes studies related to straightaways (i.e. roads, lanes, paths). We conclude by discussing the findings of this review, critiquing the methodological approaches used, and offering recommendations for future research.

The principal trend that emerges from the papers reviewed here is that clearly-marked, bike-specific facilities (i.e. cycle tracks at roundabouts, bike routes, bike lanes, and bike paths) were consistently shown to provide improved safety for cyclists compared to on-road cycling with traffic or off-road with pedestrians and other users. Marked bike lanes and bike routes were found to reduce injury or crash rates by about half compared to unmodified roadways. The finding that bicycle-specific design is important applies also to intersections with roundabouts, where it was found that cycle tracks routing cyclists around an intersection separately from motor vehicles were much safer than bike lanes or cycling with traffic. It has been suggested that the reason for high rates of bicycle-motor vehicle collisions at intersections is that motor vehicle drivers may be making “looked-but-failed-to-see” errors, whereby they search for oncoming motor vehicles but do not recognize that a cyclist is approaching because they are not looking for them [40].

abstract
provisional full report (pdf)

one thing this report makes clear to me is that you can't just lump traditional multiuse paths in with bicycle-specific cycle tracks or bike lanes when evaluating facility safety.

John Forester

I am not surprised that this has shown up in this discussion, for I have already reviewed it on my website at:
https://johnforester.com/Articles/Saf...e%20Impact.pdf

The plain fact is that because these health professionals knew nothing about bicycle transportation, they failed to recognize the errors in these studies, or, more often, in the interpretation given to the studies, problems that we bicycle transportation engineers had identified long ago. The result of correcting these errors is that the published literature makes no demonstration that bikeways reduce car-bike collisions. Some errors: The CPSC study gives the average speed of cyclists as 1.26 mph. The Kaplan study is quoted as demonstrating a lower crash rate on bike lanes when all of its data apply to bike routes, because in 1975 there were very few bike lanes in America, but many more miles of bike route. The Wachtel study is quoted as showing that right-way sidewalk cycling is not much more dangerous than roadway cycling through the same intersections, despite Wachtel's note that this is a statistical anomaly rather than accurate information. And the reviewers equate all roadway cycling with vehicular cycling.

It's not only garbage in, garbarge out, but decay into garbage of originally reasonable information.

I sent my review to the editor, who replied that I should send a concise letter instead, which I did. But they won't publish even six paragraphs without payment of $1350. Think of that: their journal publishes erroneous information, and they demand money for the corrections.

We have had much discussion of the absence of peer review in our subject. Now look at the errors that "peer" review let through. As I remarked to one committee of high review in the transportation sciences, I would be only too pleased if papers were reviewed by those who were my peers, instead of the ill-informed people who were assigned to the task.

Mos6502

So basically, the things that make the most sense logicially, are safe.

Interesting.

randya

John, that's all sour grapes on your part, because they reach a different conclusion than you have and you are so completely locked into your tunnel vision.

There are several full pages of discussion in the published report regarding the difficulties inherent in standardizing definitions for various types of facilities, deficiencies of the studies done to date, and difficulties inherent in standardizing the data.

John Forester

You can only make a reasonable statement of views after you have read the initial papers that were reviewed, the review paper, and my review of the review paper. Until you have reached the minimal reasonable level of expertise in this subject, your opinions of this type are no more than hot air. If you want to develop the level of expertise necessary for reasonable discussion, then put your mind into doing so.

randya

From the report:

It all sounds pretty reasonable to me, I think John is the one being unreasonable here. Not surprised they didn't publish his critique, it was probably full of slanderous attacks on the authors because they reached different conclusions than the Foresterologists, thus disturbing the Foresterologists faith-based approach to cycling.

John Forester

Here is the reply that I sent, and which was not downloaded to them because of the absence of money. That is, the editors never saw my letter, so far as I can see, because their program refused to download it.

And talk about slander. Have you considered what you write? The slander that occurs in this discussion comes from those who have such self-righteous faith in non-demonstrable effects that they believe accurate criticism to be slanderous.

=============
Comment on: The Impact of Transportation Infrastructure on Bicycling Injuries and Crashes: A Review of the Literature, by Reynolds, Harris, Teshke, Cripton, and Winters.

The authors admirably attempted to review only papers that scientifically demonstrated a safety effect produced by bicycle infrastructure, commonly called bikeways, and they remarked, accurately, on the scarcity of papers in this field meeting their criteria. However, the authors concluded that several types of bikeway reduced car-bike collisions when none of the papers actually so demonstrated. The authors were misled by the combination of two factors. One is the population-wide bias that safety for cyclists requires that they stick to the edge of the roadway, or off it, the performance that bikeways are designed to produce. The other is ignorance about bicycle transportation engineering, a field with literature going back to 1976. (1)

For example, the authors equated roadway cycling with vehicular cycling. Roadway cycling is any cycling on the roadway, typically done in a dangerous, unlawful and incompetent manner, while vehicular cycling is roadway cycling done in accordance with the rules of the road for drivers of vehicles. The best evidence is that vehicular cycling has a crash rate only about 25% of that of the typically incompetent cycling.

As another example, the authors attributed significant crash reduction to bike lanes in an American paper written in 1975 that combined the statistics for bike lanes and bike routes. The contribution of bike lanes to those statistics was vanishingly small, because there were almost no bike lanes in America at that time, while there were many bike routes.

The fields of bicycle transportation and cyclist safety are filled, as the authors discovered, with seriously defective papers. The first cause was the societal and legal view that the prime duty of cyclists is to stay out of the way of cars, taught largely through the motivation of fear. This produces cyclists who have great difficulty in persuading themselves to operate safely and lawfully. The second cause is the current environmental patriotism that demands facilities to attract people with that defective view of cycling but which, as the authors (if they accept my criticism) have discovered, do not make cycling significantly safer.

My detailed review of the review paper is at:
https://johnforester.com/Articles/Saf...e%20Impact.pdf

Note my statement above, that lawful, competent cycling in accordance with the rules of the road for drivers of vehicles produces a crash rate only about 25% of that for the general bicycling public. I do not know of any other safety program that presents such a large, but reasonably possible, improvement.

1: Forester, John; The Bicycle Transportation Controversy; Transportation Quarterly Vol 55 No 2, p7-17, Spring 1001

Mos6502

Even taking that into account, wouldn't the overall gist of "Results to date suggest that sidewalks and multi-use trails pose the highest risk, major roads are more hazardous than minor roads, and the presence of bicycle facilities (e.g. on-road bike routes, on-road marked bike lanes, and off-road bike paths) was associated with the lowest risk. " still be correct?

John Forester

Not quite, I think. But I was considering, as were the reviewers, reduction in crash rate produced by each kind of facility. You are considering more the existing crash rates. Yes, sidewalks and multi-use trails have high crash rates, major roads have a somewhat higher crash rate than do minor roads. Off-road bike paths are a mixed lot; what distinguishes them from multiple-use trails? And what distinguishes paths far from the roadway from paths alongside the roadway, which latter have very high crash rates, because they have the same topological relationship to the roadway as do sidewalks? And streets to be designated as bike routes have already been selected as safer than usual. And, nobody really expects that putting up bike route signs, which is the typical treatment, actually reduces crashes, though new traffic signals at some intersections would help. Much the same goes for streets on which bike lanes get built; mostly on streets that are already sufficiently wide for them. The reviewers did not find, and I know of none, studies that specifically did either before and after, or comparison of otherwise identical streets, to determine if it was the stripe itself that reduced crashes, and came up with the conclusion that the bike-lane stripe reduced crashes.

randya

the difference between multiuse paths and off-road bike paths is that pedestrians are allowed on the former, but not on the latter; if you had really read the paper, you would know that.

John Forester

It appears from much discussion here and elsewhere that, at least in America, there are no off-road bike paths that effectively keep out pedestrians. Those that do, it appears, are only those characterized as sidepaths which also have sidewalks, and it is well known that such sidepaths have a high crash rate.

genec

Has anyone peer reviewed your review of this study? Or once again do you stand alone on an isolated island with a population of one.

The Human Car

Right, car centric roadway designs do not facilitate cyclists riding their bicycles as drivers of vehicles and only encourage dangerous, unlawful and incompetent cycling by a factor of 3:1 by your best evidence.

John Forester

Environmental Health demanded $1350 to merely look at my short letter. Which I won't spend.

However, my longer critique has been posted on my website for all to read. I has been remarked that the best peer review occurs after publication, when everyone else has their chance.

I specifically sent notice to my peers, for their advice. One suggested an additional criticism of one of the papers that had been reviewed that was so bad that I passed it off simply as being inaccurate. The peer referred to his own lengthy criticism of that paper, and one surprising piece of data from it. I gave the URL and the surprising data item, which was that in America the average cycling speed calculates to 1.26 mph. These are the kinds of peer reviewed papers to which we have had to respond.

Bekologist

bwaughahahahahaha.

john, this rather exhaustive monograph, a collection and cross-analysis of bicycling studies with rather strict criteria, is compelling in its professional standard.

You recriminate with 'gigo' but your critical screed is obtusely myopic. however, as a self styled bicycle transportation ingenue your sophmoric analysis can be forgiven.

invisiblehand

I don't know what the standard is for transportation studies, but it is the case that in economics and statistics that a literature review is done by people with a long publishing record in the field. For a good set of examples, see the Journal of Economic Perspectives.

If John is right, one would expect it to have certain types of mistakes.

randya

so you're not allowed to review the literature until you've published extensively?



have you researched the publishing record of this study's authors to determine if they are allowed to review the literature yet?

invisiblehand

Allowed? Anyone can review it.

Few will listen unless the authors' familiarity is demonstrated by a series of publications. At least that is how established disciplines -- the computer science, physics and math guys down the hall agree -- work in my experience.

Maybe the authors are established. I have not read every paper and don't live as a transportation engineer. But if John's statement is correct -- I think John has a bias, but I also think he has read every referenced paper -- then he has a point.

randya

sorry, but I seriously doubt that John has personally read all 78 referenced papers cited in that report.

John Forester

Invisible Hand starts by introducing the process of peer review in normal professional disciplines and then moves on to suggest that the same "standard is for transportation studies." Indeed, in the great majority of transportation studies published in journals (as opposed to studies intended to justify some zoning change or other) I think that the same standard holds. At least I have seen no indication that it does not, for example in the papers accepted by the Transportation Research Board, of which I have been a member. That is, except for papers on bicycle transportation, which is the ideological oddity.

I know the details of the American experience in this matter. The European history may have been similar, but the details have been lost. As I have been writing, American society felt that cyclists should operate in the cyclist-inferiority manner, and the initial bikeway standards were intended to enforce this style of cycling. Initially, traffic engineers objected, foreseeing the intersection hazards that are now apparent. But political power had its way and the bikeway system was established. (The leader of the Calif. Senate told the engineering committee that bikeways would be produced no matter what.) The bikeways were designed without regard to making cycling safer (no safety investigations were done), but according to motorists' argument that the way to keep cyclists safe was to keep them at the edge of the roadway, or off it if possible. It was known before the bikeway standards were completed that the best scientific evidence demonstrated that bikeways (with the exception of long-distance trails well away from roads) could not significantly reduce car-bike collisions, and this was rapidly confirmed by the best statistical study of car-bike collisions that has ever been done.

Aside from the statistical investigator, who for years was puzzled why his study had not been applied, the only opponents were vehicular cyclists, the only people with sufficient thoughtful cycling experience to be experts in the field. But politics in the grip of the popular superstition about bicycle safety won the day. Once the standards were issued, the anti-motoring environmentalists enthusiastically endorsed the standards, because these people also believed (or said that they did) the superstition that keeping cyclists at the edge of the roadway kept cyclists safe, so that, in their anticipation, bikeway building would safely free large numbers of motorists from their bondage and greatly reduce motoring.

So the nation's policy for bicycle transportation was firmly settled on a policy of cyclist-inferiority cycling on bikeways, a policy which did not make cycling safe while allowing all to see that cyclist-inferiority cycling had the official endorsement of those supposedly acting for the safety of cyclists. But which system had no scientific support whatever; its only virtue was its popularity with people ignorant of proper cycling: motorists, the general public, and the typical bicycle rider.

So, there existed two opposite views about cycling: vehicular cycling on good roadways, and cyclist-inferiority cycling on bikeways. Although cyclist-inferiority cycling had never had any scientific support, it was both the official policy and it was believed by the general public and especially strongly by bicycle advocates. Ever since, those organizations with money to spend on bicycling affairs have funded studies that attempt, in one way or another, to demonstrate that cyclist-inferiority cycling is safer and more convenient that vehicular cycling. And they have failed.

Look at the just-issued survey of published papers that was intended to demonstrate that thesis. So few papers, after thirty years of well-funded effort, even remotely met that criterion, and, in the end, the desired thesis was not demonstrated. Surely, if there were scientific merit in the cyclist-inferiority cycling hypothesis, that merit would have been well demonstrated after all that effort to find it.

So we come to the issue of whether bicycle transportation engineering is a normal engineering or scientific discipline. First, it has to be based on vehicular cycling, or something close to that, because that is where the evidence puts safety and even convenience. But there is no money in that; all the money goes to cyclist-inferiority cycling on bikeways. I suggest that the combined incomes from cycling instruction books of John Franklin, John Allen, and I would not support one family. Therefore, despite three short-lived attempts, there has never been a journal to publish papers in this field.

So, how about other journals and their referees? You have seen the result for Environmental Health. The referees are not only without training or experience to judge papers on bicycle traffic engineering, they are hampered by believing what everybody knows about bicycling, cyclist-inferiority cycling is the only acceptable way. The errors that they make are not about public health, their field of expertise, but about details of bicycle transportation engineering that have been known for years to those familiar with the field.

One might think that the Bicycling Committee of the Transportation Research Board should have both the expertise and the freedom from bias to be the most reliable publisher of papers in bicycle transportation engineering. Sadly, that is not so. I have been a member of that committee, I have been a referee for that committee, and I have had much experience with the subject of refeering in this field. As one might expect, the members of that committee are those with professional positions in bicycle transportation. That is, they either are paid to do cyclist-inferiority work (planning, research, or similar), or they are those who pay to have that work done.

Probably because those who promote cyclist-inferiority cycling can't demonstrate its safety, and its convenience is obviously no better than any roadway cycling method, and because their incomes depend on it, these people are intensely protective of the dogma that funds them. As a referee for TRB's Bicycling Committee, I saw papers accepted with grievous scientific errors, simply because they appealed to the cyclist-inferiority belief, while I saw papers rejected, not for scientific errors, but because they challenged the cyclist-inferiority belief. At one point, the committee had to be instructed to conduct its refereeing according to the standard instructions, Rules for Referees, by Bernard K. Forscher, published in Science. And the committee still insisted on making rejections of the type specifically prohibited by Rules for Referees, just to prevent official recognition of vehicular cycling.

And now consider Environmental Health. It has published a paper with several obvious errors, obvious at first glance to persons expert in bicycle transportation engineering, and it demands, of amateurs no less, $1350 to consider for peer review a short partial correction notice.

John Forester

Don't be so silly; I thought that you had better brains than that. I have not argued that normal roadway designs "encourage dangerous, unlawful and incompetent cycling." I have argued that that that encouragement is provided both by the popular, but erroneous, view of how cycling should be conducted, and by the facilities that are designed in accordance with that view.

John Forester

No, that is correct. I read only almost all of those which were specifically referenced by the reviewers as indicating improvement in cyclist safety. Most of those were already familiar to me because they were on the subject in which I am most interested; I had alredy reviewed, or participated in reviewing, several of them.

Mos6502

Isn't this about like saying "locomotive-inferiority railroading on railways"? - you know, since putting trains on the highway would make them equal to cars...

John Forester

This looks like a good quip for cocktail parties, but I fail to understand its relevance. Of course, when I say the policy is for cyclist-inferiority cycling on bikeways I thought that it was obvious that the bikeways were the preference, but that the same cyclist-inferiority cycling was to be expected on roadways without bikeways.

Mos6502

I guess I just don't understand the reasoning that putting bikes on bikeways makes bicycles inferior.

My quip is suggesting that trains be inferior to cars, because they operate on purpose built railways, instead of the on the roads with other traffic. Obviously drawing such a conclusion (seriously) could only be achieved through some sort of non sequitur logic.