| Age | Description | Categories/units | N(%) / Mean(SD) |
---|---|---|---|---|
Health and social factors at 33y and 50y (main exposures) | ||||
 Poor self-rated health | 33y 50y | one question with 4 categories at 33y (5 categories at 50y) ranging from excellent to poor | dichotomised: ‘poor’ refers to two categories (‘fair’ and ‘poor’) combined | 1444 (13.3) 1789 (18.4) |
 Obesity | 33y 50y | body mass index (weight (kg) /height (m)2) ≥ 30 kg/m2 | No; Yes | 1227 (11.5) 2395 (25.6) |
 Depression | 33y 50y | 15 (yes/no) items at 33y (8 at 50y) from the psychological sub-scale of the Malaise Inventory | top (gender-specific) 10% defined as ‘depressed’c | 1294 (11.8) 998 (10.4) |
 Low self-efficacy | 33y 50y | 3 (yes/no) questions: feel you get what you want out of life; have free choice and control over life; run life more or less as you want to. Items summed to create a score (0–3) | defined as scores 0–2 | 3036 (29.6) 2552 (26.6) |
 Manual SEP | 33y 50y | categorized using the Registrar General’s Classification of occupations (if missing at 50y, 46y data used) | includes skilled manual and semiskilled/unskilled classes | 4082 (40.1) 3063 (32.9) |
 Not in paid employment | 33y 50y | derived from participant reports of their current main economic activity; includes unemployed, full time education/government training, temporary/permanently sick, looking after home/family, retired, other | No; Yes | 2281 (20.8) 1489 (15.3) |
 Not married/co-habiting | 33y 50y | not living with a lawful or live in partner, derived from household composition data | No; Yes | 2263 (20.5) 1975 (20.3) |
 Parenthood (number of children) | 33y 50y | all children (natural/adopted/partner’s/fostered) living in the household; identified from household composition data | dichotomised as ≥2 children living in the household | 5600 (55.5) 3129 (32.1) |
Early-life covariates | ||||
 Pre-pubertal stature | 7y | measured by trained medical staff, to the nearest inch | cm | 122.4 (5.9) |
 Hand control/ co-ordination problems | 7y, 11y, 16y | at each age recorded as: no problems (score: 0); somewhat or certainly applies (score: 1); the three variables were summed across ages | Number of ages with problem: 0 (i.e. no problem at 7y, 11y and 16y), 1, 2, 3 (problems at 7y, 11y and 16y) | 0: 6388 (57.9) 1: 3063 (27.8) 2: 1276 (11.6) 3: 308 (2.8) |
 Cognitive ability | 16y | derived age standardised score for reading and mathematics tests and converted to 0–100 scale. Average of tests used (if missing, average from 11/7y used); converted to internally standardised z-scores. | NAd | NAd |
 SEP | birth | father’s occupation at birth (if missing at 7y); categorized using the Registrar General’s (1951) Classification | 1. professional/managerial 2. skilled non-manual 3. skilled manual 4. semiskilled/unskilled/no male head | 1: 2141 (18.0) 2: 1171 (9.9) 3: 5817 (48.9) 4: 2760 (23.2) |
 Household amenities | 7y, 11y, 16y | three questions at each age on access to bathroom/indoor lavatory/hot water, scored as: sole use (0), shared (1), not available (2); the nine questions are summed across ages. | Score range: 0–18 | 1.07 (2.6) |
 Minimal parental education | birth, 7y | two questions on (i) mother and (ii) father having minimal schooling | No; Yes | 6334 (60.1) |
 Parental divorce | 33y | single question on parents ever permanently separating or divorced | No; Yes | 1672 (15.4) |