From the news report it's 95%, not 90%. Presumably the data about sample size etc. will be available when they publish. You can't reasonably expect that level of detail from a news article reporting prior to publication.
8 karma · joined December 30, 2020
https://www.businesstoday.in/current/economy-politics/oxford...
https://www.thetimes.co.uk/article/covid-vaccine-boost-for-m...