Table 1.

Information content and delivery by stage and invitation group

	Delivery	Content
	(mode, messenger, recipients, time)	Control arm	Intervention arm
Pre-invitation	Mailed 3–4 weeks prior to the appt From GP (signature and letterhead) All patients	Pre-invitation letter notifying the patient of the lung health check service Information booklet mimicking so far as possible ‘the facts’ booklets for cancer screening programmes	Identical pre-invitation letter to control Targeted information leaflet introducing the tests using a low burden approach including: - content designed to reduce fear, fatalism, stigma - explanation and diagram to show how early treatment can work - quotes from interview participants to address stigma and highlight benefit - emphasis on non-judgemental service
Invitation	Mailed 2–3 weeks prior to the appt From GP (signature and letterhead) All patients	Letter inviting patients for a lung health check including: - statement that smokers and ex-smokers are being invited - pre-scheduled appointment - contact details to cancel/rearrange/further information - information to help journey planning (map/address/stations/buses) Second copy of information booklet.	Control letter with one exception: - statement changed to say that people who have ever smoked are being invited (rather than smokers and ex-smokers specifically) Second copy of targeted information leaflet Brief essential information on the reverse side of the letter including details for requesting free copy of information booklet (phone or online)
Appointment	Run by Research Nurse All patients attending the appt	Information booklet (same as mailed previously). Nurse-led facilitation of informed decision-making	Identical to control
Reminder	Mailed ≥4 weeks after missed appt From GP (signature and letterhead) Patients who miss their appointment without cancelling	Letter re-inviting the patient for a lung health check appointment with similar content to the invitation letter	Control letter with one exception: - statement changed to say that people who have ever smoked are being invited (rather than smokers and ex-smokers specifically)