Estimating the size of the MSM populations for 38 European countries by calculating the survey-surveillance discrepancies (SSD) between self-reported new HIV diagnoses from the European MSM internet survey (EMIS) and surveillance-reported HIV diagnoses among MSM in 2009 - Marcus, Ulrich; Hickson, Ford; Weatherburn, Peter; Schmidt, Axel J. (BMC Public Health, 2013)