Table 1.

Baseline data collection

Section	Fields included
Consent	Consent to participate in Bug Watch (required). Permission to be contacted for qualitative interviews; for data to be linked to the Health Survey for England; to be contacted about a urinary tract infection substudy (optional).
Contact details	ID number (from invitation letter). Name. Email address. Postal address.
Demographics	Date of birth. Sex. Country of birth. Ethnic group. Work status (employed, in education, unemployed, retired and so on). Full or part time work. Is a healthcare worker.
General health	Long term illnesses or health problems. Recurrent urinary tract infections. Currently pregnant; which trimester. Smoking status. Seasonal influenza vaccine in the last year. EQ-5D-3L.
GP consultations	Number of GP consultations in last 12 months.
Antibiotics	Ever been prescribed antibiotics; number in last 12 months. Ever been prescribed antibiotics but thought it was not the right treatment. When last took antibiotics; were they prescribed (if not, where from); were all taken. Ever asked for an antibiotic prescription; was it given; needed to persuade. Which conditions think can be treated with antibiotics. Understanding of term ‘antibiotic resistance’.
Oral health	Rate dental health (global item). Has dentures. Dental symptoms in last 12 months. Problems caused by mouth/teeth/ dentures in last 12 months (impact on quality of life).
Household composition	Number of adults (aged 16+). Number of children, number to be registered (up to 4).

NB, Questions are filtered and adapted based on previous responses so that they are only shown to participants when relevant. For example, ‘Currently pregnant’ is not shown if sex is given as male. GP, General Practitioner.