Table S1.

Codebook descriptions of individual themes. Collaborative codebook by core qualitative group using consensus methods

Domain	Individual themes of interest	Description of code
1. General health perceptions	a. General sense of self and wellness	Feeling unwell/under par in a nonspecific or specific sense. Feeling less than normal. Perception of self, for example, related to external appearance
	b. Lack of confidence in one’s body	General feeling that their body could “let them down” – puts little trust in their body. Feels vulnerable or dependent on medical personnel. For example, risk of falling; or sudden onset of symptoms when away from help
	c. Poor response to treatment	Prescribed treatment ineffective (or giving only temporary relief) in general or for particular symptoms. Adverse effects
	d. Vulnerability to infection or secondary illness	A perception that one is more vulnerable to acquiring infection and is affected for longer by infections, for example, colds or secondary conditions such as cancers, diabetes, hypertension, and so on
2. Impact on function	a. Level of physical function	Cannot do same activities, or same activities to desired level – including sports/interests – because of symptoms of vasculitis. A general slowness. Also include discussions of one’s ability to exercise and perform to the desired levels
	b. Personal mobility	Personal mobility problems – relating to physical capabilities, not specific to any activity or task. Plus walking locally, for example, to shops or around neighborhood, descriptions of being housebound. Does not include transportation
	c. Scope for travel	Perceived restrictions on traveling away from home because of potential need for informed medical care, or risks due to reduced immunity – especially as cannot receive a live vaccination
	d. Household tasks	Work, housework, gardening (yard work). Difficulty with carrying out “normal” everyday tasks required to keep home environment in order. Maintenance, cleaning or tidying around the house, garden/yard, or work – if that occupies most days
	e. Treatment consumes time/focus	Effect on time management, for example, sticking to a routine for taking treatment. Lots of time taken up with thinking about, or actively engaged with, treatment or monitoring of the condition. Dependent on medicine/medical personnel
	f. Adaptation	Need to do things differently, because of effects of AAV, in order to accomplish tasks. Requires walking aids/supports or other devices (eg, hearing aids), to facilitate ADL
	g. Hobbies and interests	Impact on (loss of) hobbies/interests (not necessarily social) due to AAV. Could include range of things like gardening, playing an instrument, amateur dramatics, dancing, and stamp collecting. Might also include activities/interests involving technology: computer, camera, and so on
	h. Use of everyday transport	Issues relating to the ability to get around in vehicles – cars, trains, busses, and so on
	i. Eating and drinking	Finds it hard to eat: difficulties swallowing, fills up quickly. Difficulties with certain foods – having to be careful with what they eat. Physical difficulty of getting food/drink to mouth. Restriction in alcohol
	j. Everyday technology	Problems with using telephone, television, and so on – chiefly because of sensory problems (sight/hearing)
	k. Washing self	Difficulty with washing (all over) – mainly because of hand arm function
	l. Dressing and undressing	Difficulty with putting on particular clothes avoids some or needs help because of effect of AAV
3. Psychological	a. Uncertainty/concerns about future	Concern about what might happen to self or dependents if the condition (or ability to cope) worsens including flares or shortened life/death. Difficulties or changes in relation to future plans
	b. Fear, anxiety, stress	Easily or acutely becomes fearful or anxious; or has generalized feeling of anxiety: low threshold (since AAV). Cannot cope with any extra stress – sense that they have no spare capacity for dealing with stresses in life. Generalized feeling of “being a worrier” – worries creep into most situations or thoughts – implies this is not normal for them (i.e., compared to past or compared with how they have tended to think of themselves in the past)
	c. AAV dominates	Concerns or uncertainties are AAV or related symptoms serving as a barrier to getting on with, or enjoying, life. Feeling as though life has been put on hold. AAV dominates thoughts.
		A feeling of loss of control over one’s own life – due to unpredictability of AAV – and its severity and/or demands of treatment
	d. Self-efficacy	Attitude to disease. Feeling that life is a struggle – weighed down [by symptoms ± low energy] but battling on against it OR conversely having a strong sense of self-efficacy
	e. Information and knowledge	Descriptions of the presence or absence of information about vasculitis (what it is like, prognosis, treatments). This node assumes that the person knows they have vasculitis. Any content speaking more specifically to uncertainty/fear about the future should be coded at uncertainty
	f. Support	Descriptions of the person’s perceived level of support – could relate to social relationships, a relationship with god/religion
	g. Depression low mood	Aware of overt depression or perceived difficulty with feeling positive – constant or intermittent (but there in the background). Constant concerns about/coping with AAV removes fun and enjoyment from everyday life. Life has little purpose. Realities of living with/concerns about/coping with AAV can affect fun and enjoyment from everyday life
	h. Anger and irritation	Either due to frustration with disease or its treatment or direct effects of medication, for example, steroids
4. Social perceptions	a. Visibility of condition or side effects	Feeling self-conscious or embarrassed about a sign/symptom of the condition or treatment obvious to other people
	b. Empathy and emotional connections	Perception that others (partner, family, friends) do or do not understand (how bad/ill/tired they feel). Can be coupled with reluctance to explain too much detail to others (thereby compounding the problem) or thinking that others do not believe them. May socialize more with others who have vasculitis – who understand
	c. Source of other people’s worry	Perception that friends or family are anxious on their behalf – or are worried that they might become “a responsibility”/burden. Or might be contagious
5. Social contact	a. Impact on social life	Content relating to less energy for socializing, reduced social contact in person, improved social relationships, and social isolation (vulnerability, loss of confidence in social situations)
	b. Social activities anparticipation	Unable to engage in social activities that the person wants to or was doing, before the illness struck, for example, sports and community participation including organized religion
	c. Adaptations to facilitate social life	AAV-related difficulties (eg, mobility problems/sensory impairment/fatigue) mean that social occasions require pacing or special planning
	d. Quality of communication	Impaired hearing/voice problems make communications difficult
	e. Sex and intimate relationships	Difficulties within relationships and with sex either because of AAV or its treatments
6. Social role	a. Occupation or finances	Worry concerned with their ability to do/or get back to doing, their job (“pull their weight”); worries about losing their job – because of effects of AAV on their ability to do their specific type of work, or any kind of work (“hold down a job”). Might include financial worries – if they were unable to continue in work (or to the same level). Loss of income – perhaps additional costs incurred, for example, house or transport adaptations, because of AAV. Could also include unpaid work
	b. Family and family planning	Worry about the effect that their AAV is having on their family: changing roles (their increased dependency); how family will manage if their work is affected (reduced/lost) or if they die. Feeling like a burden on their family. Effects on decisions about family size. Increasing stress and conflict within family
	c. Dependency on others	Needs help from others/partner to do certain tasks/go outside the home (may be contrasted with former role where others were more dependent on them)
	d. Role identity and status	Unable to be helpful/useful to others (as in the past) – associated with a sense of letting others down as it relates to significant others, family, or work associates. Change in status at work or in society
7. Symptoms	a. Fatigue	Fatigue, exhaustion, or energy drain, which can be intermittent, sudden, or persistent/constant. Has “normal” level of energy some (hours or days) of the time, then suddenly overcome with fatigue/tiredness/weakness. Or persistent lack of energy, fatigue/tiredness/weakness over many days, weeks, or months
	b. Cognition and poor concentration	Difficulties with focusing on a topic for any length of time. Generally feels distracted or thoughts “drift off” “in a fog.” Trouble making decisions and understanding others or situations
	c. Issues related to body weight	Weight loss, gain, or distribution, causing concern – could be secondary to lost appetite or steroids
	d. Sleep symptoms	Difficulty getting to sleep, staying asleep, getting enough sleep. For whatever reason (including psychological or physical discomfort). Difficulties with sleeping – either getting off to sleep, or persistent or early waking – aggravating tiredness – for whatever reason (including psychological or physical discomfort)
	e. Temperature instability	Sweating, shivering, including night sweats: excessive sweating at night – often while asleep – for no good reason
	f. Skin and nail problems	Abnormal rash/marks/blotches/lumps/ulcers, affecting the skin, including signs of bleeding into skin (including under nails). Added swelling of the skin and hair changes and mucous membranes and Raynaud’s syndrome
	g. Earache and hearing difficulties	Ear infections/sense of blocked ears/impaired hearing/need for hearing aid/painful ears (internally)/feeling of pressure
	h. Upper respiratory tract	Constant feeling of nose or sinuses being blocked, congested, pressured, or running. Bleeding – in quantity – from the nose, on more than one occasion. Sore throat or problems with voice. Sinus infections or repeated need for treatment of some kind
	i. Eye symptoms and affected sight	Eye pain or irritation. Impaired or lost sight. Bleeding into eye. Cataracts. Threat/fear of losing sight. Can also include watery, itchy, or dry eyes
	j. Cardiorespiratory symptoms	Shortness of breath/sense that breathing is labored/pain associated with breathing. Wheezing or coughing. Coughing up blood. Chest pains
	k. Gastrointestinal symptoms	Diarrhea, vomiting, nausea, bloating
	l. Muscle symptoms	Pain perceived as coming from muscle(s) related or unrelated to activities. Including cramps including aches or pains in lower or upper back. Perceived muscle weakness or tiredness and less ability to control specific muscle actions. If related to lower limbs may provoke falls
	m. Numbness and nerve symptoms	Hypersensitivity, burning pains, or numbness along the path of a nerve
	n. Joint symptoms	Ache/pain, stiffness, swelling (of joints), range of movement, increased warmth perceived as coming from, or in, joints – one joint or many. When at rest or following activities
	o. Kidney and urinary tract	Passing blood in urine or frequency or dysuria (pain or difficulty passing water) and kidney problems
	p. Appetite	Loss of appetite. No interest in food or finds it hard to eat: difficulties swallowing, fills up quickly. (new) Difficulties with certain foods – having to be careful with what they eat
	q. Sense of taste	References to inability to taste food
	r. Feeling unsteady or faint	Has difficulty maintaining balance when either standing on one spot for any length of time, or after initially standing up. Or gait affected. Possibly associated with sense of dizziness or lightheadedness. Also include descriptions of feeling faint or fainting
	s. Pain	Pain in arms and hands, pain in feet and legs: low-grade aching through to severe. Intermittent or persistent/constant. Could relate to muscles, joints, or nerves, and should be double coded as appropriate. Any mention of pain in the face, upper sinuses, or head. Generalized pain without specified cause or location

Abbreviations: AAV, antineutrophil cytoplasmic antibody-associated vasculitis; ADL, activities of daily life.