| |
|
The report presents the standardised results for minority
ethnic groups in the form of ratios to the general population. The
actual values of the standardised means or percentages are not shown.
See Risk ratio. |
|
Anthropometric |
See Body mass index (BMI), Mid-upper arm |
|
measurements |
circumference and Waist-hip ratio. |
|
Asthma |
Children aged 2-15 were asked if they had ever been
told by a doctor that they had asthma. They were also asked a series
of questions about experience of wheezing or whistling in the chest,
with or without cold or flu, or breathlessness. These questions
have been used to categorise children for tables shown in Chapter
13. |
|
Blood analytes |
See Cholesterol, HDL-cholesterol, LDL-cholesterol,
C-reactive protein, Ferritin, Fibrinogen, Glucose, Glycated haemoglobin,
Haemoglobin, Triglycerides, IgE and House dust mite specific IgE. |
|
Blood pressure |
Systolic (SBP) and diastolic (DBP) blood pressure were
measured in informants aged 5 and above using a standard method
(see Appendix B for measurement protocol). In adults, high blood
pressure is defined as SBP >=140 mmHg or DBP >=90 mmHg or
on antihypertensive drugs. In addition, informants were asked whether
they had ever been diagnosed as having high blood pressure ('reported
high blood pressure'). |
|
Body mass index |
Weight in kg divided by the square of height in metres.
In adults, if the resulting value is more than 25.0 but no greater
than 30.0, the condition is defined as 'overweight'. If it exceeds
30.0, the condition is defined as 'obese'. If it exceeds 40.0, the
condition is defined as 'morbid obesity'. |
|
Breathlessness |
See Asthma. |
|
Cardiovascular disease |
Informants were classified as having cardiovascular
disease (CVD) if they reported ever having any of the following
conditions diagnosed by a doctor (or a nurse in case of blood pressure):
angina, heart attack, stroke, heart murmur, irregular heart rhythm,
'other heart trouble', high blood pressure or diabetes. |
|
Cholesterol (total) |
An important component of blood lipids transported in
plasma.For the purpose of this survey total cholesterol was considered
to be raised at a level of 5.0 mmol/l or over. See also HDL-cholesterol,
|
|
|
LDL-cholesterol. |
|
Cotinine |
Cotinine is a metabolite of nicotine. It is one of several
biological markers that are indicators of smoking. In this survey,
it was measured in saliva. It has a half-life in the body of between
16 and 20 hours, which means that it will detect regular smoking
(or other tobacco use such as chewing) but may not detect occasional
use if the last occasion was several days ago. Anyone with a saliva
cotinine level of 15 nanograms per millilitre or more is highly
likely to use tobacco. |
|
C-reactive |
C-reactive protein is the major protein indicating inflammation
|
|
protein |
activity in acute illness in humans. It is also a marker
of cardiovascular risk. Since no recommendation for a C-reactive
protein threshold is made in the literature, those with a C-reactive
protein level in the range defined by the top quintile of the general
population (>3.7 mg/l for men, >4.9 mg/l for women) are considered
for the purpose of this report as having 'high' C-reactive protein.
|
|
DINE |
The Dietary Instrument for Nutrition Education (DINE)
was developed by the Imperial Cancer Research Fund's General Practice
Research Group to assess dietary and fibre intake in the population.
The versions of DINE that were developed by the DINE team for minority
ethnic groups were adapted for use in this survey. (See Chapter
9 for more detail.) |
|
ECG |
An electrocardiographic (ECG) measurement was taken
as an objective measurement to assess heart disease. Its findings
are strictly related to heart disease manifestations such as for
example death of heart muscle (infarction). See also Minnesota
coding. |
|
Equivalised household income |
Income was not included in the Health Survey series
until 1997. Making precise estimates of household income, as is
done for example in the Family Resources Survey, requires far more
interview time than was available in the Health Survey. Household
income was thus established by means of a card (see Appendix A)
on which banded incomes were presented. Information was obtained
from the head of the household or their partner. Initially they
were asked to state their own (head and partner) aggregate gross
income, and were then asked to estimate the total household income
including that of any other persons in the household. Household
income can be used as an analysis variable, but there has been increasing
interest recently in using measures of equivalised income that adjust
income to take account of the number of persons in the household.
Methods of doing this vary in detail: the starting point is usually
an exact estimate of net income, rather than the banded estimate
of gross income obtained in the Health Survey. The method used in
the present report was as follows. It utilises the widely used McClemens
scoring system, described below. |
|
|
1.
|
A score was allocated to each household member, and
these were added together to produce an overall household McClemens
score. Household members were given scores as follows. |
|
|
|
| First adult (head) |
0.61 |
| Spouse/partner of head |
0.39 |
| Other second adult |
0.46 |
| Third adult |
0.42 |
| Subsequent adults |
0.36 |
| Dependent aged 0-1 |
0.09 |
| Dependent aged 2-4 |
0.18 |
| Dependent aged 5-7 |
0.21 |
| Dependent aged 8-10 |
0.23 |
| Dependent aged 11-12 |
0.25 |
| Dependent aged 13-15 |
0.27 |
| Dependent aged 16+ |
0.36 |
|
|
|
2. |
The equivalised income was derived as
the annual household income divided by the McClemens score. |
|
|
3. |
This equivalised annual household income was attributed
to all members of the household, including children. |
|
|
4. |
Black Caribbean, Asian and Chinese households were
grouped together and then ranked by equivalised income, and tertiles
t1 and t2 identified. Because income was obtained in banded form,
there were groups of households with the same income spanning the
tertiles. Rather than arbitrarily split these groups the 'tertiles'
were defined as 'households with equivalised income up to t1', 'over
t1 up to t2', and over t2. |
|
|
5. |
All households were then allocated to the appropriate
tertile, and all individuals within a household were allocated to
the equivalised household income tertile to which their household
had been allocated. |
|
|
As noted above, the tertiles were derived
from the incomes of Black Caribbean, Asian and Chinese households
rather than the general population. This is because household income
amongst minority ethnic groups is, on average, considerably lower
than that for the general population. Categorising minority ethnic
groups to tertiles based on the general population income distribution
would give only very small sample sizes in the highest income tertile
for most minority ethnic groups. Since this would reduce our likelihood
of observing associations between ethnicity, income and health,
the alternative approach, of basing tertiles on the income distribution
of the Black Caribbean and Asian minority ethnic groups, was adopted.
The Irish were not included in the sample used to define the tertiles
because their income distribution was close to that of the general
population and because the relatively large sample size of this
group would have skewed the results. |
| Fasting blood sample |
In addition to the non-fasting blood sample, adults
aged 35 or over were asked to provide a fasting blood sample. Informants
were asked not to consume food or drink, except water, in the 8
hours previous to this sample being collected. The blood analytes
from the fasting sample include: triglycerides, LDL-cholesterol
and glucose. |
| Ferritin |
Ferritin is the main form in which iron is stored in
the liver, spleen and bone marrow. A small fraction of ferritin
circulates in the bloodstream and this fraction correlates well
with body iron status. |
| FEV1 |
Forced Expiratory Volume: the amount of air (in litres)
that a subject can breathe out of his/her lungs during the first
second of an expiration with maximal effort, starting from full
inspiration. |
| Fibrinogen |
Fibrinogen is a soluble protein involved in the blood
clotting mechanism. Prospective population studies have established
that fibrinogen is an independent predictor for ischaemic heart
disease and stroke. |
| FVC |
Forced Vital Capacity: the volume of gas (in litres)
delivered during an expiration made as forcefully and as completely
as possible starting from full inspiration. |
| GHQ12 |
The General Health Questionnaire (GHQ12) is a scale
designed to detect possible psychiatric morbidity in the general
population. The questionnaire contains 12 questions about the informant's
general level of happiness, depression, anxiety and sleep disturbance
over the past four weeks.Reference: Goldberg D, Williams PA. User's
Guide to the General Health Questionnaire. NFER-NELSON, 1988. |
| Glucose |
Glucose (blood sugar) was measured from the fasting
blood sample. New WHO guidelines for diagnosing diabetes adopted
in the UK include a fasting plasma glucose threshold of 7.0 mmol/l. |
| Glycated haemoglobin |
The percentage of glycated haemoglobin is the percentage
of haemoglobin in the circulation to which glucose is bound. It
reflects the prevailing level of blood glucose during approximately
three months preceding the measurement. |
| Haemoglobin |
The iron-containing molecule in red blood cells. Low
haemoglobin (anaemia, defined as a level of haemoglobin of less
than 12.0 g/dl) is most commonly caused by iron deficiency. |
| HDL-cholesterol |
In a normal individual, high density lipoprotein (HDL)
constitutes approximately 20% of total plasma cholesterol. For the
purpose of this survey HDL-cholesterol was considered low at a level
of less than 1 mmol/l. See also Cholesterol. |
| Head of household |
The head of household was defined as the household member
who owned or rented the property, or was a man married to or cohabiting
with a woman who was the owner/renter (i.e. husband/male partner
took precedence). If there was equal claim to be head of household,
male took precedence over female and, where they were of the same
sex, older took precedence over younger. |
| Height and age |
For the children's analysis in Chapter 13, those variables
that are |
| standardisation |
strongly associated with age and height have been 'height
and age standardised' when drawing comparisons between groups. This
has been done using linear regression models, with ethnic group,
age and height entered into the regression equation. The regression
coefficients for individual minority ethnic groups represent the
height and age standardised absolute difference in mean value for
the outcome variable compared with the general population. |
| High blood pressure |
See Blood pressure. |
| Hormone replacement |
The treatment of women with pharmacological doses of
oral |
| therapy (HRT) |
oestrogen taken alone or with an oral progestogen to
alleviate menopause symptoms. Most women on HRT are postmenopausal
(i.e. stopped menstruating) or perimenopausal (in transition). Younger
women (before age 45) may also be prescribed HRT following a hysterectomy,
also termed surgical menopause, or because of an early natural menopause. |
|
House dust mite
|
Antibody produced as a specific response to house dust
mite, a |
| specific IgE |
common inhalant allergen (see IgE). |
| Household |
A household was defined as one person or a group of
people who have the accommodation as their only or main residence
and who either share at least one meal a day or share the living
accommodation. |
| IgE |
Immunoglobulin E, the antibody responsible for the immediate
type of immune response. A raised serum concentration of IgE is
found in people with an atopic predisposition. |
| Income |
See Equivalised household income. |
| Ischaemic heart disease |
Informants were classified as having ischaemic heart
disease (IHD) if they reported ever having angina or a heart attack
diagnosed by a doctor. |
| LDL-cholesterol |
Low density lipoprotein (LDL)-cholesterol was calculated
by the laboratory using the Friedwald formula: |
|
LDL-
|
cholesterol = total cholesterol - (HDL-cholesterol
+ (triglycerides/2.2))
Triglyceride measurement must be below 4.5 mmol/l for this formula
to be used. LDL-cholesterol was considered high at a level of 3.0
mmol/l or over. See also Cholesterol.
Reference: Friedwald WT,Levy RL, Fredrickson DS. Estimation of
the concentration of low density lipoprotein cholesterol in plasma
without the use of preparative ultracentrifuge. Clin Chem 1972;
18:499-502. |
| Linear regression |
Linear regression is a statistical modelling technique
used to investigate the independent effects of two or more factors
('independent' or 'predictor' variables) on a 'dependent' or 'outcome'
variable. Linear regression was used in Chapter 13 of this report
to estimate the differences between minority ethnic groups and the
general population after controlling (or standardising) for age
and height. |
| Logistic regression |
Logistic regression was used to investigate the effect
of two or more independent or predictor variables on a two-category
(binary) outcome variable. The independent variables can be continuous
or categorical (grouped) variables. The parameter estimates from
a logistic regression model for each independent variable give an
estimate of the effect of that variable on the outcome variable,
adjusted for all other independent variables in the model.
Logistic regression models the log 'odds' of a binary outcome variable.
The 'odds' of an outcome is the ratio of the probability of its
occurring to the probability of its not occurring. The parameter
estimates obtained from a logistic regression model have been presented
as odds ratios for ease of interpretation.
For continuous independent variables, the odds ratio gives
the change in the odds of the outcome occurring for a one unit change
in the value of the predictor variable.
Parameter estimates for categorical independent variables
have been presented in two ways. In some cases, one category of
the categorical variable has been selected as a baseline or reference
category, with all other categories compared to it.. Therefore there
is no parameter estimate for the reference category and odds ratios
for all other categories are the ratio of the odds of the outcome
occurring between each category and the reference category, adjusted
for all other variables in the model. In other cases, where there
is no obvious reference category, the odds ratios for a given category
of a categorical independent variable gives the change in the odds
of the outcome occurring compared to the overall odds ('to average').
The statistical significance of independent variables in models
was assessed by the likelihood ratio test and its associated p value.
95% confidence intervals were also calculated for the odds ratios.
These can be interpreted as meaning that there is a 95% chance that
the given interval for the sample will contain the true population
parameter of interest. In logistic regression a 95% confidence interval
which does not include 1.0 indicates the given parameter estimate
is statistically significant. |
| Lung function |
Lung function tests were used to monitor the respiratory
health of children from minority ethnic groups aged 7-15. See also
FEV1, FVC, PEF. |
| Major accident |
Accident about which a doctor was consulted or a hospital
visited. |
| Mean |
Unless otherwise specified, means in this report are
arithmetic means. |
| Mid-upper arm |
The circumference taken at the mid-point between the
shoulder and |
| circumference |
elbow of the child's bare left arm using an insertion
tape, as described in Appendix B. |
| Minnesota coding |
In this report the analysis of the ECG results involve
automatic interpretation and Minnesota coding. The Minnesota coding
was originally designed to determine prevalence information of cardiovascular
disease in epidemiological studies. See also ECG.
Reference: Prineas RJ, Crow RS, Blackburn H. The Minnesota Code.
Manual of electrocardiographic findings. John Wright, 1982. |
| Minor accident |
Accident which caused pain or discomfort for over 24
hours but about which a doctor was not consulted nor a hospital
visited. |
| Morbid obesity |
See Body mass index. |
| Obesity |
See Body mass index. |
| Overweight |
See Body mass index. |
| Percentile |
The value of a distribution which partitions the cases
into groups of a specified size. For example, the 20th percentile
is the value of the distribution where 20 percent of the cases have
values below the 20th percentile and 80 percent have values above
it. The 50th percentile is the median. |
| PEF |
Peak Expiratory Flow: the maximal flow in litres per
minute recorded during a forced expiration. In healthy subjects
this index reflects the calibre of central airways and the force
exerted by the expiratory muscles. |
| p value |
A p value is the probability of the observed difference
(or higher) occurring due to chance alone. A p value of less than
5% is conventionally taken to indicate a statistically significant
result (p<0.05). It should be noted that the p value is dependent
on the sample size, so that with large samples differences or associations
which are very small may still be statistically significant. Results
should therefore be assessed on the magnitude of the differences
as well as on the p value itself. The p values given in this report
are based on the assumption of a simple random sample and do not
take into account the complex sampling design of the survey. |
| Ratio of means |
See Risk ratio |
| Risk ratio |
The risk ratio for a group is the ratio of the prevalence
in that group to the prevalence in the general population (for persons
of the same sex). The term is usually used to refer to an adverse
health condition or risk factor, but has also been used for ratios
involving other kinds of proportion. In all chapters reporting adult
data, the data were standardised before the ratios were computed.
In Chapter 13, which deals with children, the data have not been
age-standardised, and risk ratios were computed on the basis of
the unstandardised data.
Similar ratios can be computed for statistics other than percentages,
such as means or rates. The report refers to such ratios as ratios
of means, or rate ratios, or standardised ratios.
As with prevalences, ratios of means or rates for adults are based
on standardised data, for children on unstandardised. |
| SDQ |
The Strengths and Difficulties Questionnaire (SDQ) is
designed to detect behavioural, emotional and relationship difficulties
in children aged 4-16. The questionnaire is based on 25 items: 10
strengths, 14 difficulties and one neutral item. The 25 items are
divided into 5 scales of 5 items each: hyperactivity, emotional
symptoms, conduct problems, peer problems and prosocial behaviour.
Each SDQ item has three possible answers which are assigned a value
0,1 or 2. The score for each scale is generated by adding up the
scores on the 5 items within that scale, producing scale scores
ranging from 0 to 10. A 'Total Deviance' score is derived from the
sum of scores from each of the scales except the Prosocial Behaviour
scale, producing a total score from 0 to 40.
The SDQ correlates highly with the Rutter questionnaire and the
Child Behaviour Checklist, both of which are long established behavioural
screening questionnaires for children that have been proved valid
and reliable in many contexts and correlate highly with one another.
The SDQ is shorter than these screening instruments and is the first
to include a scale focusing on positive behaviour: the Prosocial
Behaviour Scale.
Reference: Goodman R. The Strengths and Difficulties Questionnaire:
A Research Note. J Child Psychol Psychiatry 1997; 38: 581-586. |
| Sensitivity |
The proportion of actual cases of a given condition
that are correctly identified by a test designed to identify that
condition. A test has high sensitivity if there are few false negatives.
See also Specificity. |
| Social class of |
A social class was assigned on the basis
of the occupation of the head |
| head of household |
of household using the Registrar General's Standard
Occupational Classification. Occupations are assigned to six social
class categories: |
| |
|
| Social Class |
Occupations |
| I |
|
Professional occupations |
| II |
|
Managerial and technical occupations |
| III |
Skilled occupations |
|
(IIINM) |
|
(non-manual) |
|
(IIIM) |
|
(manual) |
| IV |
Partly skilled occupations |
| V |
|
Unskilled occupations |
|
|
| |
In this report, these six social classes have been combined
into two: non-manual (I, II, IIINM) and manual (IIIM, IV, V).
In households where the head of household was not interviewed the
social class of the head of household was derived from information
obtained from their spouse or partner. Heads of households who were
in the armed forces, whose occupation was not adequately described
or who were full-time students were not allocated a social class
and are not shown separately in the tables. They are, however, included
in the total column. |
| Social support |
The perceived social support scale, originally used
in the Health and Lifestyle Survey, was based on seven questions
about physical and emotional aspects of social support. Informants
were asked about the amount of support and encouragement they received
from family friends. These questions were combined into a single
scale categorising informants as having 'a severe lack', 'some lack'
or 'no lack' of social support.
Reference: Cox BD et al. The Health and Lifestyles Survey.
The Health Promotion Research Trust, London, 1987. |
| Specificity |
The proportion of cases that do not have a given condition
that are correctly identified by that test as not having the condition.
A test has high specificity if there are few false positives. See
also Sensitivity. |
| Standardisation |
In this report, standardisation refers to standardisation
(or 'adjustment') by age (see Age standardisation), unless
otherwise specified, as in Chapter 13, where standardisation by
height is also used. |
| Standardised ratio |
See Risk ratio. |
| Standard Occupational |
The Registrar General's Standard Occupational Classification
|
| Classification(SOC) |
classifies occupations in terms of the type and level
of skill required to carry out the main work activity. There are
several hundred Occupational Unit Groups. These are grouped at successive
higher levels of aggregation, culminating in the nine Major Groups: |
| |
1. |
Managers and Administrators |
| |
2. |
Professional Occupations |
| |
3. |
Associate Professional and Technical Occupations |
| |
4. |
Clerical and Secretarial Occupations |
| |
5. |
Craft and Related Occupations |
| |
6. |
Personal and Protective Service Occupations |
| |
7. |
Sales Occupations |
| |
8. |
Plant and Machine Operatives |
| |
9. |
Other Occupations |
| |
Reference: Volume 3 Standard Occupational Classification.
OPCS, HMSO, London, 1991. |
| Tertiles |
Tertiles are percentiles which divide a distribution
into thirds. |
| Triglycerides |
Triglycerides or simple fats, are molecules composed
only of fatty acids and glycerol. They were analysed from the fasting
blood sample. Triglycerides were considered high at a level of 1.6
mmol/l or above. |
| Unit of alcohol |
A unit of alcohol is 8 gms of ethanol, and is the
amount contained in half a pint of ordinary beer or lager, or in
a small glass of wine, or in a measure of spirits. |
| Waist-hip ratio |
Waist-hip ratio (WHR) is defined as the waist circumference
divided by the hip circumference, i.e. waist girth (m)/ hip girth
(m). A raised WHR has been taken to be 0.95 or more in men and 0.85
or more in women. |
| |
|
