Continuing to Debunk Aldred
DEBUNKING MORE OF PROFESSOR ALDRED’S CLAIMS
by Charlie Edwards
This research study by Professor Rachel Aldred claims that inside the LTN areas there was approximately a 70% reduction in absolute injury numbers and also approximately a 70% reduction in risk per trip for walking, cycling and car travel alike. There was no evidence of a change in injuries on LTN boundary roads
In 2020 there was a pandemic but the study fails to address or even mention that the pandemic took place and that accidents across the Great Britain dropped dramatically. Aldred’s taken the figures from March to September 2020 when we were on lock down. These accident rates wouldn’t obviously be meaningful against figures from Oct to Dec 2018 & 2019 when car usage was much higher and when there were fewer daylight hours.
In Table One of her report, Professor Aldred shows that figures for 5 out 8 of the data sets have a P value of much greater than 0.05. Some more than 12 times greater. This means the data is not significant, no respectable academic would publish this data let alone bother to use it in report.
(See below for the average accident figures for 2018 -202 from the government website. https://www.gov.uk/government/statistical-data-sets/reported-road-accidents-vehicles-and-casualties-tables-for-great-britain#casualties-in-reported-road-accidents-ras30)
There’s no mention that the speed limits changed from 30 to 20 mph. As Aldred states she only uses ’killed or seriously injured figures’ so the figures would have reduced anyway compared to the previous years, even if the LTNs haven’t been introduced.
Professor Aldred references her own papers so there’s just this ever expanding recycling of poor quality studies being used as reference to churn out more poor quality papers. Sometimes she references Cairns et al, which is a 20 year old paper of 275 pages. It’s not about LTNs but city centre closures to traffic, pre-sat nav era. Even then Cairns found that the boundary roads became congested when the roads were closed.
The report has been used to mislead the public by a number of newspapers journalists with numerous ‘errors’ or overstatements in what’s been written. (The Standard The Guardian ) A MASS SPREAD OF FAKE NEWS.
