For the record
The drug sold as Keytruda, used in cancer treatment, was approved in 2015, not last year as we said (Cancer: how to kill a killer, the New Review, 4 November, page 27).
The First World War is thought to have cost 15-20 million lives. The 37 million figure we used included the wounded (“May hails UK’s ‘closeness’ with Europe ahead of armistice events”, 4 November, News, page 2).
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