the Guardian. ‘Pfizer Vaccine Has 91% Efficacy for up to Six Months, Trial Shows’, 1 April 2021. http://www.theguardian.com/world/2021/apr/01/pfizer-vaccine-has-91-efficacy-for-up-to-six-months-trial-shows.

Bar-Zeev, N., & Kochhar, S. (2020). Expecting the unexpected with COVID-19 vaccines. The Lancet Infectious Diseases, 0(0). https://doi.org/10.1016/S1473-3099(20)30870-7

Hilda Bastian, PhD. (2021, February 6). Unofficial unnamed AstraZeneca insider says they are doing the interim analysis for the US trial of the Oxford vaccine. AstraZeneca spokesperson says 4-6 weeks till data release. Https://t.co/VUHgbHN02d One is wrong? Or they’ll release only when have FDA minimum follow-up? Https://t.co/LgjfX8AIti [Tweet]. @hildabast. https://twitter.com/hildabast/status/1357862227106095105

Isaacson, Walter. ‘Opinion | I Was Part of a Trial for Pfizer’s Covid-19 Vaccine. It’s a Miracle for Genetic Medicine.’ Washington Post. Accessed 6 March 2021. https://www.washingtonpost.com/opinions/i-took-the-pfizer-covid-19-vaccine-its-a-miracle-for-genetic-medicine/2020/11/09/77e652d0-22bf-11eb-952e-0c475972cfc0_story.html.

Carl T. Bergstrom. (2021, January 31). A somewhat technical thread about measuring vaccine efficacy. We’re used to the notion that certain properties of tests for disease depend on prevalence: Positive and negative predictive value do, for example, whereas sensitivity and specificity do not. [Tweet]. @CT_Bergstrom. https://twitter.com/CT_Bergstrom/status/1355762090078703621

Carl T. Bergstrom. (2020, December 5). I don’t have a background in medical ethics but this makes me uncomfortable unless it was very clearly explained to study participants at enrollment, and to some degree even then. H/t @RMCarpiano https://t.co/WUE1mXgjJG https://t.co/yLXkxIa5O8 [Tweet]. @CT_Bergstrom. https://twitter.com/CT_Bergstrom/status/1335152266840424449

CNN, A. V., Holly Yan and Christina Maxouris. (n.d.). FDA won’t ‘cut corners’ to approve a Covid-19 vaccine, commissioner says. CNN. Retrieved 12 August 2020, from https://www.cnn.com/2020/08/10/health/us-coronavirus-monday/index.html

Lipsitch, M., Perlman, S., & Waldor, M. K. (2020). Testing COVID-19 therapies to prevent progression of mild disease. The Lancet Infectious Diseases, 0(0). https://doi.org/10.1016/S1473-3099(20)30372-8

The study. This sounds very similar to the placebo effect, so I wonder if they have checked to see what effects they would find if they picked activities previously classified as neutral.