GambleAware-backed study warns of selection bias in gambling harm research 14th May 2021 | By Robert Fletcher Research commissioned by British gambling charity GambleAware has warned that online surveys of gambling harm face a “particular risk” of selection bias, which can inflate the numbers of those experiencing harm if not properly accounted for. However, it added that measurement of gambling-related harm should still generally should move to online surveying – adjusted through less frequent face-to-face “benchmarks” – due to high costs and sample-size issues in face-to-face surveys. Authored by Professor Patrick Sturgis and Professor Jouni Kuha from the London School of Economics, the study looked at how methodological differences between surveys affect the accuracy of estimates of gambling harms.