Sir, – In Gerry Thornley’s important article discussing brain-damage risk in rugby (“Rugby in the firing line as brain damage is linked to contact sport”, October 29th), Prof Tim Lynch addressed Prof William Stewart’s recent study that found a 15-times increased odds ratio for Motor Neurone Disease (MND) in former international rugby players.
Prof Lynch noted the fact that the study gave no figures on the number of cases of MND in the 412 rugby players studied (although this number can be inferred from the analysis), and subsequently described the study as “hard to interpret”.
Prof Lynch did not comment on the fact that there were zero cases of MND found in the 1,236 study participants that did not play rugby. Nor did he note that the reported ratio of 15 was calculated by artificially adding a single case to the group of non-players; therefore most likely under-representing the true risk.
Perhaps the focus should be on developing policy based on the best available evidence, instead of seeking to kick to touch on this issue by continually saying “the jury is still out”.
– Yours, etc,
Dr LUKE CONROY,
Institute of Health
Informatics,
University College London.