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Taking advantage of the high prevalence of mobile phones, we deployed a national SMS-poll and collected data about individual-level health and health-seeking behavior throughout the outbreak from 6694 individuals from March to June 2015 in Liberia. Using propensity score matching to generate balanced subsamples, we compared outcomes in our survey to those from a recent household survey (the 2013 Liberian Demographic Health Survey). We found that the matched subgroups had similar patterns of delivery location in aggregate, and utilizing data on the date of birth, we were able to show that facility-based deliveries were significantly decreased during, compared to after the outbreak (<jats:italic>p<\/jats:italic>\u2009&lt;\u20090.05) consistent with findings from retrospective studies using healthcare-based data. Directly assessing behaviors from individuals via SMS also enabled the measurement of public and private sector facility utilization separately, which has been a challenge in other studies in countries including Liberia which rely mainly on government sources of data. In doing so, our data suggest that public facility-based deliveries returned to baseline values after the outbreak. Thus, we demonstrate that with the appropriate methodological approach to account for different population denominators, data sourced via mobile tools such as SMS polling could serve as an important low-cost complement to existing data collection strategies especially in situations where higher-frequency data than can be feasibly obtained through surveys is useful.<\/jats:p>","DOI":"10.1038\/s41746-018-0055-z","type":"journal-article","created":{"date-parts":[[2018,9,21]],"date-time":"2018-09-21T20:54:45Z","timestamp":1537563285000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":19,"title":["Tracking health seeking behavior during an Ebola outbreak via mobile phones and SMS"],"prefix":"10.1038","volume":"1","author":[{"given":"Shuo","family":"Feng","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4368-0045","authenticated-orcid":false,"given":"Karen A.","family":"Gr\u00e9pin","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5346-7259","authenticated-orcid":false,"given":"Rumi","family":"Chunara","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"297","published-online":{"date-parts":[[2018,10,2]]},"reference":[{"key":"55_CR1","doi-asserted-by":"publisher","first-page":"S88","DOI":"10.5588\/pha.16.0099","volume":"7","author":"F Shannon","year":"2017","unstructured":"Shannon, F. et al. 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