His list currently sits at 216. It's big, and broad, and it's comprised entirely of anecdotal evidence. Anecdotes are generally regarded as the weakest form of evidence, in terms of scientific inquiry.
This is because anecdotal evidence is subject to a few key problems:
- A small sample size, that isn't necessarily representative of a larger sample.
- Confirmation bias, the tendency to ignore evidence that disagrees with one's beliefs, and to place too much weight on evidence that agrees with one's beliefs
- It's subject to 'Cherry picking' - in this instance, the anti-wind lobby regularly points to a few cases of anecdotal claims of ill-health around wind turbines, but ignore the many communities that have seen no issues whatsoever.
The size and scale of Chapman's list is truly incredible. In that vein, I've drawn his list up into an infographic, to better illustrate the clear issues with the unbridled over-use of anecdotal reports as primary evidence of an issue.
[PDF] - 0.2 MB
[PNG] - 0.6 MB - 2197 x 1587
[JPG] - 1.2 MB - 2197 x 1587
Click to embiggen