The self-reported postal questionnaires covered demographic and socioeconomic information, nutritional assessment (food frequency questionnaire), mental health (K-10 and CES-D scales), physical activity (PASE questionnaire), medical and surgical history, general health and quality of life, cognition, respiratory symptoms, medicine use, employment history and occupational exposure calendar, social support (Duke social support index), sleep, tocbacco use, alcohol consumption, health service utilization, oral health questionnaire and hearing assistance.

Clinic measurements of respiratory function (spirometry), cardiovascular function (heart rate and blood pressure), cognition (MMSE and ARCS), sensory measures (visual acuity, audiometry, olfaction using sniffing sticks and vibration sense using biothesiometry), obesity (BMI and waist hip ratio), functional performance (functional reach test, timed up and go, and grip strength), physical activity (using a pedometer worn for 7 days), bone density (heel ultrasound), vaccination history and non-steroidal anti-inflammatory drug use.

Blood collection for haematological, biochemical, and genetic tests. Samples have been assayed for full blood count, electrolytes, urea/creatinine, liver function tests, fibrinogen, urate, CRP, and fasting lipids and blood glucose. DNA has been isolated and microarray analysis been performed on Affymetrix Kaiser platform; imputation to Hap Map and to 1000 Genomes reference panels has also been performed and is available for genome-wise association studies (GWAS).

The participants' study data was also linked with local and national health information databases and hospital records to provide follow-up on use of prescription medication, health service utilization and hospitalizations, morbidity and mortality.

The self-reported postal questionnaires covered demographic and socioeconomic information (economic hardship items, health insurance, pet ownership), sedentary time, mental health (K-10, CES-D, Berkman Symes social network index, McMaster family assessment device, satisfactiion with life scale, novelty seeking, optimism), medical and surgical history (including falls), gastrointestinal pain (based on Rome criteria), general health and quality of life, medicine use, social support, sleep, and tobacco use.

The participants' study data was also linked with local and national health information databases and hospital records to provide follow-up on use of prescription medication, health service utilization and hospitalizations, morbidity and mortality.

The self-reported postal questionnaires covered demographic and socioeconomic information, mental health (melancholia and resilience), medical and surgical history, medicine use, tobacco use, alcohol, retirement, physical activity (PASE) and cognition (MACQ scale). 

Those scoring high and a random sample of those scoring normally on cognition (MACQ) were invited to clinic for: full olfaction testing with sniffing sticks and scratch and sniff cards (UPSIT), full cognitive screen, mental health (DASS 21 and CES-D); these were also asked to provide a blood sample

The participants' study data was also linked with local and national health information databases and hospital records to provide follow-up on use of prescription medication, health service utilization and hospitalizations, morbidity and mortality.