An evaluation of changes in opinion from an expert workshop on turbidity in drinking water supplies and acute gastrointestinal illness

Several epidemiological studies have found associations between turbidity in drinking water supplies and acute gastrointestinal illness, although these results have been controversial. This project sought to critically evaluate these epidemiological studies through a workshop of multidisciplinary subject matter experts. Pre- and post-workshop surveys were conducted to assess any changes in opinion occurring after the one-day workshop where issues identified in the literature review were discussed. Changes were mostly small, non-significant shifts toward less favourable views of the studies. The only significant change was a shift weak agreement to weak disagreement with the statement that more should be done to ensure US drinking water quality. Responses to questions differed significantly by affiliation, discipline, and by role in the study. The survey results indicate that the workshop did not produce consensus among the participants. The survey provided a means of documenting differences in opinions expressed by all workshop attendees.