Online market research panel members as controls in case–control studies to investigate gastrointestinal disease outbreaks: early experiences and lessons learnt from the UK – ERRATUM. Issue 12 (19th July 2018) - Mook, P.; McCormick, J.; Kanagarajah, S.; Adak, G. K.; Cleary, P.; Elson, R.; Gobin, M.; Hawker, J.; Inns, T.; Sinclair, C.; Trienekens, S. C. M.; Vivancos, R.; et al.