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Multivariable analysis of symptoms or signs of cases compared with controls with symptom and sign data excluded from 1, 3, 6 and 12 months prior to diagnosis/index date. Mutual adjustment of all symptoms and signs in using a conditional logistic regression model stratified by time prior to date of diagnosis. Models additionally adjusted for comorbidities using van Walraven weighted score. For the complete set of results, see online supplemental appendix 5.
