Article History
Received: 5 October 2017
Accepted: 25 June 2018
First Online: 11 July 2018
Ethics approval and consent to participate
: The study was approved by the Human Research Ethics Committee of the Faculty of Health, University of Cape Town (ref. 309/2013). As this was an anonymised secondary data source retrospectively spanning 40 years, the requirement for individual informed consent was accepted as non-applicable. The data were made available by TEBA Ltd., Johannesburg, a private company (), and are not publicly available. There was no restriction on publication.
: Prof. Ehrlich has written expert reports for plaintiff lawyers in silicosis litigation proceedings. The other authors report no competing interests.
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