Meta RCT’s Meta-analysis of your experiments Randomized Controlled Trials Your own A/B tests or MVT experiments Quantitative & Qualitative data Web analytics analysis, on-site surveys, usability testing, heat- & scroll maps, 1-1 interviews, data mining at sales and/or customer service. Market Research Heuristic evaluations, external reports/sources, meta-research Expert opinion & case studies Asking just one person (not a customer), HiPPO or ZEBRA if (s)he likes the website. Not evidence Anecdotes, gut feeling, forums, competitors, Linkedin Lunatics, A/B test results websites, Awards, etc. Risk of Bias Quality of Evidence Lower Strong Weak Higher