Table 1 Questions and response options in BCS70 and NCDS and new variables created following data harmonisation
1970 BCS cohort | 1958 NCDS cohort | Harmonised measures | |||||
|---|---|---|---|---|---|---|---|
Age (Respondent) | Question | Categories or scale | Age (Respondent) | Question | Categories or scale | Variable | Categories or scale |
Birth (midwife) | Birthweight of baby Gestational age | ...lbs. ...ozs. or ...gm ...days/...months | Birth (midwife) | Birth weight Gestation period | ...lbs. ...ozs. ...days/...months | Birthweight (kg) for gestation (weeks) z-scores a | 1st quarter (lowest) 2nd quarter 3rd quarter 4th quarter (highest) |
Birth (mother) | Mother’s age at birth | ...years | Birth (mother) | Mother’s age at birth | ... years | Mother’s age at birth | 19 or less years 20–34 years 35 or more years |
Birth (mother) | Does the mother smoke now? If no: Did she ever smoke? If yes: How long ago did she stop? How much did she smoke? Has she smoked during this pregnancy? | Yes/No Yes/No Years/Months 1–4/5–14/15–24/25 or more/Not known Yes/No/Not known | Birth (mother) | Did the patient smoke as many as one cigarette a day during the 12 months before the start of this pregnancy? If so, how many per day during that period? If smoked one per day: Did the patient change her smoking habits during this pregnancy? Record changes in the table below and month of pregnancy change made. | Did not smoke as many as 1 per day Number smoked per day in that period No change Gave up/Month of pregnancy/Number per day smoked after change Cut down/Month of pregnancy/Number per day smoked after change Increased/Month of pregnancy/Number per day smoked after change | Mother smoked during pregnancy | No Stopped prior or during the pregnancy Smoked during the pregnancy |
Birth (mother) | Occupation of husband If self-employed: If not self-employed: Employed at present Unemployed at present | Actual job, Description of job Employing 25 or more persons/Employing fewer than 25 persons Supervising others/Not supervising others | Birth (mother) | What was the husband’s occupation? If self-employed: Does he employ 10 or more persons? If not self-employed: Does he supervise others (e.g. foreman, manager, charge-hand)? | Actual job / Industry Yes/No Yes/No | Father’s social class at birth | Non-manual Manual No father in household |
Birth (mother) | Was {cohort member} breastfed partly or wholly even for a few days? | Yes - for less than 1 month Yes - for 1 month or more but less than 3 months Yes - for 3 months or more Yes but cannot remember for how long No, was not breastfed at all Not known | Birth (mother) | Was the child breastfed (partly or wholly) as a baby? | No Yes - under 1 month Yes - over 1 month Don’t know | Has been breastfed | Less than 1 month or never Breastfed 1 or more months |
10 (cohort member) | Friendly Maths Test: A multiple choice test including arithmetic, number skills, fractions, algebra, geometry, and statistics. The Shortened Edinburgh Reading Test (Godfrey Thompson Unit 1978): A test of word recognition, which examined vocabulary, syntax, sequencing, comprehension and retention. | Test scores ranged between 1 and 72 (included 72 items) Test scores ranged between 0 and 67 (included 67 items) | 11 (cohort member) | Arithmetic/Mathematics Test: involving numerical and geometric work. Reading Comprehension Test: involving selection of words which appropriately completed sentences | Test scores ranged between 1 and 40 (included 40 items) Test scores ranged between 0 and 35 (included 35 items) | Cognitive ability (maths, reading) z-scores at 10/11 b | … z- score |
16 (mother) | What age did your teenage girl have her first menstrual period? | Before 11th birthday When aged 11 Aged 12 Aged 13 Aged 14 Aged 15 or more Not yet commenced Commenced but don’t know age | 16 (mother) | At what age did she have her first menstrual period? | Before 11th birthday When aged 11 Aged 12 Aged 13 Aged 14 Aged 15 or more Not yet commenced Commenced but don’t know age Don’t know whether commenced | Age at menarche (years) | … years |
16 (medical examination) | Height in cm, to nearest 0.5 cm Height in feet and inches, to nearest 1/4 in. Weight in kilograms, to nearest 0.1 kg Weight in pounds and ounces | … cms … feet … inches … kg … pound … ounces | 16 (medical examination) | Height in cm Height in feet and inches Weight | … cm … ft. … in … kg … st … lb. | BMI at 16 (weight [kg]/height [m]2) | … kg/m2 |
16 (cohort member) | Which of the following most nearly describes you? | I have never smoked a cigarette I have only ever tried smoking once or twice I used to smoke sometimes, but I don’t know I smoke and I would like to give it up I do not want to give up smoking | 16 (cohort member) | How many cigarettes do you usually smoke in a week? | None, don’t smoke Less than 1 a week Between 1 and 9 a week Between 10 and 19 a week Between 20 and 29 a week Between 30 and 39 a week Between 40 and 49 a week Between 50 and 59 a week 60 or more a week | Has smoked at 16 | No Yes |
16 (cohort member) | If you have had any alcoholic drink since this time last week, on how many days did you do so? | … number of days | 16 (cohort member) | How long is it since you had an alcoholic drink (beer, wine, spirits, etc.)? | Less than 1 week 2–4 weeks 5–8 weeks 9–12 weeks Over 12 weeks Uncertain/Can’t remember Never had one | Has had an alcoholic drink the week prior the age 16 interview | No Yes |
16 (cohort member) | During the past year, which of the following {team/individual/other listed} sports did you play, in school and out of school, when they were in season, and how often? | At least once a week At least once a month | 16 (cohort member) | Below is a list of things which many people do in their spare time. You will probably only do a few of these. Please show by ringing one of the numbers for each one whether this is something that you do often, sometimes, never or hardly ever. If it is something that you would like to do but don’t have the chance, please ring 4. - Playing outdoor games and sports - Swimming - Playing indoor games and sports | Often Sometimes Never or hardly ever Like to but no chance | Frequency of exercise at 16 | Monthly or less often Weekly (or often) |
16 (mother) | Below is a series of descriptions of behaviour sometimes shown by young people. Please say whether, in respect of your teenager, the descriptions certainly applies, applies somewhat of doesn’t apply. - Often worried, worries about many things - Often appears miserable, unhappy, tearful or distressed - Tends to be fearful or afraid of new things or new situations | Doesn’t apply Applies somewhat Certainly applies | 16 (mother) | Below are a series of descriptions of behaviour often shown by young people. Please ask the informant about each one and ring the appropriate number to show the degree to which this description is true of the study child. - Often worried, worries about many things - Often appears miserable, unhappy, tearful, or distressed - Tend to be fearful or afraid of new things or new situations | Doesn’t apply Applies somewhat Certainly applies | Emotional/Neurotic score at 16 (range: 0–6) c | … score (0 = none apply / 6 = all apply) |
30 (cohort member) | How tall are you without shoes? Before you were pregnant, what was your weight? / What is your current weight without clothes on? | Meters and Centimetres Feet and inches Kilograms Stones and pounds | 33 (cohort member) | How tall are you without shoes? Before you were pregnant, what was your weight? / What is your current weight without clothes on? | Meters and Centimetres Feet and inches Kilograms Stones and pounds | BMI at 30/33 (weight [kg]/height [m]2) | … kg/m2 |
30 (cohort member) | Would you say that..? | You’ve never smoked cigarettes You used to smoke cigarettes but don’t at all now You now smoke cigarettes occasionally but not every day You smoke cigarettes every day | 33 (cohort member) | Do you smoke cigarettes at all nowadays? Have you ever smoked cigarettes regularly - by regularly I mean at least one cigarette a day for 12 months or more? | Yes No Yes No | Has smoked at 30/33 | Never Ex-smoker Smoker |
30 (cohort member) | How often do you have an alcoholic drink of any kind? Would you say you had a drink..? | On most days 2 to 3 days a week Once a week 2 to 3 times a month Less often or only on special occasions Never now a days Have never had an alcoholic drink | 33 (cohort member) | How often do you have an alcoholic drink of any kind? | Most days 1, 2 or 3 times a week 1, 2 of 3 times a month Less often/only on special occasions Never | Frequency of alcohol consumption at 30/33 | Weekly (once to most days a week) Monthly (one to three times a month) Less often or never |
30 (cohort member) | Do you regularly take part in any of the activities on this card - that is at least once month, for most of the year? How often do you take part in any activity of this type? | Yes No Every day or most days 4–5 days a week 2–3 days a week Once a week 2–3 times a month Less often | 33 (cohort member) | Do you regularly take part in any of the activities on this card - that is at least once month, for most of the year? How often do you take part in any activity of this type? | Yes No Can’t say Every day or most days 4–5 days a week 2–3 days a week Once a week 2–3 times a month Less often Can’t say | Frequency of exercise at 30/33 | Weekly (once to most days per week) Monthly (two to three times a month) Less often or never |
30 (cohort member) | Malaise inventory, 24-items measuring psychological distress | Yes No | 33 (cohort member) | Malaise inventory, 24-items measuring psychological distress | Yes No | Has experienced depression symptoms at 30/33 d | No (score 0–7) Yes (score of 8 or higher) |
30 (cohort member) | Have you ever had or been told that you had a problem with your periods? Have you ever been told that you had any other gynaecological problems? | Yes No Yes No | 33 (cohort member) | Have you ever suffered from or been told you had..? - Persistent trouble with periods - Other gynaecological problems | Yes Only when pregnant No | Has suffered periods or other gynaecological problems by 30/33 | No Yes |
30 (cohort member) | Are you currently taking the contraceptive pill? Have you ever taken the contraceptive pill? | Yes No Yes No | 42 (cohort member) | Are you currently taking the contraceptive pill? Have you ever taken the contraceptive pill? | Yes No Yes No | Has ever taken contraceptive pill by 30/42 | No Yes |
33, 38 (cohort member) | Has anyone you were having a sexual relationship with ever become pregnant? / have you been pregnant? What was the result of this pregnancy [for the nth baby]? | Yes No Live birth Still birth Miscarriage Abortion Still pregnant | 33, 42 (cohort member) | Has anyone you were having a sexual relationship with ever become pregnant? / have you been pregnant? What was the result of this pregnancy [for the nth baby]? | Yes No Live birth Still birth Miscarriage Abortion Still pregnant | Has no live born children (nulliparous) | No Yes |
38 (cohort member) | Which of the things on this card best describes what you were doing {date of last interview}{next}? What is your (main) job? What do you mainly do in your job? What does the firm or organisation you work for mainly make or do (at the place where you work)? | Full-time paid employee (30 or more hours a week) Part-time paid employee (under 30 hours a week) Full-time self-employed Part-time self-employed Unemployed and seeking work Full-time education On a government scheme for employment training Temporarily sick/disabled Permanently sick/disabled Looking after home/family Wholly retired Other (specify) Open text Open text Open text | 42 (cohort member) | Which of the things on this card best describes what you are currently doing? What is your (main) job? What do you mainly do in your job? What does the firm or organisation you work for mainly make or do (at the place where you work)? | Full-time paid employee (30 or more hours a week) Part-time paid employee (under 30 hours a week) Full-time self-employed Part-time self-employed Unemployed and seeking work Full-time education On a government scheme for employment training Temporarily sick/disabled Permanently sick/disabled Looking after home/family Wholly retired Other (specify) Open text Open text Open text | Social class at 38/42 | Non-manual Manual Not in paid employment |