The UCLA California Health Interview Survey uses telephone interviews to collect data.  The reported results may over or underestimate the actual situation in Yolo County, because the county is a small subset of the data, because the survey relies on the candor of respondents and because telephone surveys tend to under represent portions of the population lacking consistent access to telephone service, who may also be less likely to have health insurance.  The survey had a sample size of 203 children (ages 12 and under), 94 adolescents (ages 12-17), and 844 adults (18 and over) for Yolo County.