TILDA data collection

TILDA data were collected using three methods. A computerised-assisted personal interview, which included questions related to socio-demographic characteristics, physical, cognitive, mental and behavioural health, lifestyle, social support and participation, health and social care utilisation including medication usage, was administered by trained interviewers. The self-completed questionnaire asked more sensitive questions, including loneliness, stress, anxiety, worry, quality of life (QoL), ageing perception and alcohol use. Participants attended a health centre for a comprehensive physical assessment.

OA was self-reported by asking ‘Has a doctor ever told you that you have any of the following conditions?’ If respondents answered yes to having arthritis, they were then asked ‘Which type or types of arthritis do you have? Response choices included ‘osteoarthritis’, ‘rheumatoid arthritis’ or ‘other types of arthritis’. Those reporting a diagnosis of OA were retained for this analysis.

Presence of pain was asked by the following question ‘Are you often troubled with pain?’ If the respondent replied ‘Yes’, they progressed to a question ‘How bad is the pain most of the time?’ Response options included ‘mild’, ‘moderate’ or ‘severe’. Respondents were asked in which part of the body pain was most severe. Pre-specified areas included back, hips, knees, feet, mouth/teeth, ‘other’ and ‘all over’. ‘Other’ referred to areas not pre-specified in the interview question.