•A new venue-based degree measure is introduced to adjust reported network size.•Computed venue-informed RDS estimates for population HIV/syphilis seroprevalence are used.•Venue-informed RDS estimates had smaller variance than the standard reported size.•Venue-informed RDS estimates demonstrate reduced bias compared to the standard reported size.•Venue attendance may provide a better performed degree measure for RDS estimates. We introduce a new venue-informed network degree measure, which we applied to respondent-driven sampling (RDS) estimators. Using data collected from 746 young MSM in 2014–2016 in Chicago, IL, and Houston, TX, we estimated the population seroprevalence of HIV and syphilis and risk/protective behaviors, using RDS estimates with self-reported network size as a standard degree measure as well as our proposed venue-informed degree measure. The results indicate that the venue-informed degree measure tended to be more efficient (smaller variance) and less biased than the other measure in both cities sampled. Venue attendance-adjusted network size may provide a more reliable and accurate degree measure for RDS estimates of the outcomes of interest.