Abstract Background: At the UCSF breast screening clinic, intake surveys are sent to women with upcoming mammogram appointments to obtain their demographic data, comorbidities, and assess breast cancer risk (family history, biopsy history). Many patients complete surveys online before their visit. For those who do not, a staff member is present to assist with survey completion on a tablet in-clinic. Methods: Data was collected from 10,755 patients from December 2012–May 2018. To assess if different survey modalities capture different demographic groups, we analyzed these submissions, comparing responses completed by patients online before visits and in-clinic with assistance. Results:On average, 48% of invited patients complete a survey. Of respondents 76% completed surveys before visits and 24% completed surveys in-clinic. Both methods captured electronic data that was summarized and presented to clinicians for clinical decision support. Compared to the in-clinic group, a before group patient was more likely to be white, married, and have at least a college education. The before group included a smaller proportion of patients who were Black/African American, Hispanic/Latina, and 65 years or older. Furthermore, a greater proportion of the before group reported 2 or more comorbidities. The before population reported more often having fair or poor health over the preceding 30 days. While these differences were statistically significant, it is important to put some of these results into perspective: while only 24% of survey responses were collected in-clinic, 59.1% of all Black/African American responses and 33.5% of all Hispanic/Latina responses were represented in this group. Before group (N=7869) In-clinic group (N=2886)P valueWhite64.43%55.79%<0.0001Black/African American3.57%10.91%<0.0001Hispanic/Latina7.96%10.91%<0.0001Aged 65 or older29.84%39.54%<0.0001Married66.40%56.10%<0.0001College educated or more79.93%66.87%<0.00012 or more diagnosed comorbidities38.18%30.32%<0.0001Poor or Fair health over last 30 days10.41%5.45%<0.0001 Conclusions/Future Directions: 1) Online surveys are completed more often by traditionally well-represented groups. Offering staff supported electronic surveys in-clinic improves the total yield and diversity of patients who complete surveys. More research is required to see the impact of income levels. 2) We did not anticipate a greater incidence of fair or poor health over the last 30 days or the higher number of patients reporting 2 or more comorbidities in the before group. This could result from the before group having better access to health care, and more familiarity with health surveys, but more detailed study is needed. 3) We will investigate further issues of health care trust, familiarity, and access to adjust our clinic practices. As more studies move surveys entirely online, we need to identify and address factors that prevent patients from completing surveys before appointments. Alternative survey modalities must be made available in accessible ways and integrated into routine clinical practice. Citation Format: Shibley WP, Dreher N, van 't Veer L, Acerbi I, Fiscalini AS, Keane H, Esserman LJ, Athena Breast Health Network Investigators and Advocate Partners. Comparing characteristics of patients who fill out online surveys before visits with patients who fill out surveys in-clinic with staff assistance at the UCSF breast screening clinic [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P5-13-17.