# Article related High prevalences of disseminated neoplasia in the Baltic tellin Limecola balthica in the Wadden Sea, published in Diseases of Aquatic Organisms, DOI: 10.3354/dao03448. ## Installation Data have been analyzed using R (Rcore team 2019). ## Description of the data set This data set reported the occurrence of disseminated neoplasia in the Baltic telling Limecola balthica. #### First column: dates of sampling (dd/mm/yyyy) #### Second column: names of sampling location #### Third column: coordinates of sampling location #### Fourth column: type of sediment at the sampling location #### Fifth column: Stage of the disease, 0: individual not affected by disseminated neoplasia to 4: individual showing the most advanced stage of the disease. For description about the stage of the disease, please refer to Christensen et al. (1974) and Pekkarinen 1993). #### Sixth column: mean density of the baltic tellin at the sampling site #### Seventh column: standard error (SE) associated to the mean density. Christensen DJ, Farley CA, Kern FG. 1974. Epizootic neoplasms in the clam Macoma balthica (L.) from Chesapeake bay. JNCI J Natl Cancer Inst. 52(6):1739–1749. Pekkarinen M. 1993. Neoplastic diseases in the Baltic Macoma balthica (Bivalvia) off the Finnish coast. J Invertebr Pathol. 61(2):138–146. ## Analyses Total prevalence of disseminated neoplasia was defined as the percentage of affected bivalves at each sampling site. We tested for differences in prevalence between sampling sites using a G-test of goodness-of-fit. Prevalences of each stage of the disease were determined at each sampling site and the relationship between the total prevalence of the disease and its severity was tested by using linear regressions between both variables.