Nwaru, Bright I.Simpson, Colin R.Soyiri, Ireneous N.Pillinger, RebeccaAppiagyei, FrancisRyan, DermotCritchley, HilaryPrice, David BHawrylowicz, Catherine M.Sheikh, Aziz2018-07-042018-07-042018-06Nwaru, B I, Simpson, C R, Soyiri, I N, Pillinger, R, Appiagyei, F, Ryan, D, Critchley, H, Price, D B, Hawrylowicz, C M & Sheikh, A 2018, 'Exogenous sex steroid hormones and asthma in females : protocol for a population-based retrospective cohort study using a UK primary care database', BMJ Open, vol. 8, no. 6, e020075, pp. 1-5. https://doi.org/10.1136/bmjopen-2017-0200752044-6055RIS: urn:7506F42F6F741D71D91D78F44D208965http://hdl.handle.net/2164/10703This work was supported by Asthma UK, grant number: AUK-IG-2016-346. BIN, INS, CRS and AS were in addition support by the Farr Institute and Asthma UK Centre for Applied Research. BIN acknowledges the support of Knut and Alice Wallenberg Foundation and the Wallenberg Centre for Molecular and Translational Medicine, University of Gothenburg, Sweden.5222947engR Medicine (General)Asthma UKAUK-IG-2016-346R1Journal article10.1136/bmjopen-2017-02007586