Karyotaki, E., Kemmeren, L., Riper, H., Twisk, J., Hoogendoorn, A., Kleiboer, A., Mira, A., Mackinnon, A., Meyer, B., Botella, C., Littlewood, E., Andersson, G., Christensen, H., Klein, J. P., Schröder, J., Bretón-López, J., Scheider, J., Griffiths, K., Farrer, L., Huibers, M. J. H., Phillips, R., Gilbody, S., Moritz, S., Berger, T., Pop, V., Spek, V., & Cuijpers, P. (2018). is self-guided internet-based cognitive behavioural therapy (iCBT) harmful? An individual participant data meta-analysis. Psychological medicine, 48(15), 2456–2466. http://access.bl.uk/ark:/81055/vdc_100070088094.0x00003e