A cross-sectional data set of a workforce company, plus another health survey, in New Zealand during the 1990s,
data(xs.nz)A data frame with 10529 observations on the
following 64 variables.
For binary variables, a "1" or TRUE
means yes,
and "0" or FALSE means no.
Also, "D" means don't know,
and "-" means not applicable.
The pregnancy questions were administered to women only.
regnuma numeric vector, a unique registration number. This differs from their original registration number, and the rows are sorted by their new registration number.
study1a logical vector, Study 1 (workforce) or Study 2?
agea numeric vector, age in years.
sexa factor with levels F and M.
pulsea numeric vector, beats per minute.
sbpa numeric vector, systolic blood pressure (mm Hg).
dbpa numeric vector, diastolic blood pressure (mm Hg).
cholesta numeric vector, cholesterol (mmol/L).
heighta numeric vector, in m.
weighta numeric vector, in kg.
fh.heartdiseasea factor
with levels 0, 1,
D.
Has a family history of heart disease
(heart attack, angina, or
had a heart bypass operation) within the immediate
family (brother, sister, father or mother,
blood relatives only)?
Note that D means: do not know.
fh.agea factor, following
from fh.heartdisease,
if yes, how old was the family member when
it happened (if
more than one family member, give the age of the
youngest person)?
fh.cancera factor with levels 0, 1,
D.
Has a family history of cancer within the immediate
family (blood relatives only)?
Note that D means: do not know.
heartattacka numeric vector, have you ever been told by a doctor that you have had a heart attack ("coronary")?
strokea numeric vector, have you ever been told by a doctor that you have had a stroke?
diabetesa numeric vector, have you ever been told by a doctor that you have had diabetes?
hypertensiona numeric vector, have you ever been told by a doctor that you have had high blood pressure (hypertension)?
highchola numeric vector, have you ever been told by a doctor that you have had high cholesterol?
asthmaa numeric vector, have you ever been told by a doctor that you have had asthma?
cancera numeric vector, have you ever been told by a doctor that you have had cancer?
acnea numeric vector, have you ever received treatment from a doctor for acne (pimples)?
sunburna numeric vector, have you ever received treatment from a doctor for sunburn?
smokepassivea numeric vector, on average,
how many hours each week (at work and at home) would you
spend near someone who is smoking?
(put "0" if none)
smokeevera numeric vector, have you ever smoked tailor-made or roll-you-own cigarettes once a week or more? A 1 means yes and 0 means no.
smokenowa numeric vector, do you smoke tailor-made or roll-you-own cigarettes now? A 1 means yes and 0 means no.
smokeagequita factor,
if no to smokenow, how old were you when
you stopped smoking?
Using as.numeric(as.character(smokeagequit))
will work for those values which are not
as.character(smokeagequit) == "-".
smokeyearsa numeric vector,
if yes to smokeever, for how many years altogether
have you smoked tailor-made or roll-you-own cigarettes?
smoketailormadea numeric vector, how many tailor-made cigarettes do you smoke each day?
smokeweekpacka numeric vector, how many
packets of roll-your-own tobacco do you use
each week?
(put "0" if none)
smokepacketsizea numeric vector,
what size packets of roll-your-own tobacco do you
usually buy?
("0" means don't smoke roll-your-owns,
else 25g or 30g or 35g or 50g)
drinkmontha numeric vector, do you drink alcohol once a month or more?
drinkfreqweeka numeric vector,
if yes to drinkmonth, about how often do you
drink alcohol (days per week)?
Note: 0.25 is once a month,
0.5 is once every two weeks,
1 is once a week,
2.5 is 2-3 days a week,
4.5 is 4-5 days a week,
6.5 is 6-7 days a week.
Further note: 1 can, small bottle or handle of beer or home brew = 1 drink, 1 quart bottle of beer = 2 drinks, 1 jug of beer = 3 drinks, 1 flagon/peter of beer = 6 drinks, 1 glass of wine, sherry = 1 drink, 1 bottle of wine = 6 drinks, 1 double nip of spirits = 1 drink.
drinkweeka numeric vector,
how many drinks per week, on average.
This is the average daily amount of drinks multiplied
by the frequency of drinking per week.
See drinkfreqweek on what constitutes a 'drink'.
drinkmaxdaya numeric vector, in the last three months, what is the largest number of drinks that you had on any one day? Warning: some values are considered unrealistically excessive.
eggsa numeric vector, how many eggs do you eat a week (raw, boiled, scrambled, poached, or in quiche)?
chocbiscuitsa numeric vector, how many chocolate biscuits do you usually eat in a week?
pregnanta factor, have you ever been pregnant for more than 5 months?
pregfirsta factor, if
yes to pregnant, how old were you when your first
baby was born (or you had a miscarriage after 5 months)?
preglasta factor, how old were you when your last baby was born (or you had a miscarriage after 5 months)?
babiesnumeric, how many babies have you given birth to?
moodya numeric vector, does your mood often go up or down?
miserablea numeric vector, do you ever feel 'just miserable' for no reason?
hurta numeric vector, are your feelings easily hurt?
fedupa numeric vector, do you often feel 'fed up'?
nervousa numeric vector, would you call yourself a nervous person?
worriera numeric vector, are you a worrier?
worrya numeric vector, do you worry about awful things that might happen?
tensea numeric vector, would you call yourself tense or 'highly strung'?
embarrasseda numeric vector, do you worry too long after an embarrassing experience?
nervesa numeric vector, do you suffer from 'nerves'?
nofrienda numeric vector,
do you have a friend or family member that you
can talk to about problems or worries that you may have?
The value 1 effectively means "no",
i.e., s/he has no friend or friends.
depresseda numeric vector, in your lifetime, have you ever had two weeks or more when nearly every day you felt sad or depressed?
exerviga numeric vector, how many hours per week would you do any vigorous activity or exercise either at work or away from work that makes you breathe hard and sweat? Values here ought be be less than 168.
exermoda numeric vector, how many hours per week would you do any moderate activity or exercise such as brisk walking, cycling or mowing the lawn? Values here ought be be less than 168.
feethoura numeric vector, on an average work day, how long would you spend on your feet, either standing or moving about?
ethnicitya factor with 4 levels,
what ethnic group do you belong to?
European = European (NZ European or
British or other European),
Maori = Maori,
Polynesian = Pacific Island Polynesian,
Other = Other (Chinese, Indian, Other).
sleepa numeric vector, how many hours do you usually sleep each night?
snorea factor with levels 0, 1,
D.
Do you usually snore?
Note that D means: do not know.
cata numeric vector, do you have a household pet cat?
doga numeric vector, do you have a household pet dog?
handa factor with levels
right = right,
left = left,
both = either.
Are you right-handed,
left-handed,
or no preference for left or right?
numhousean ordered factor with 4 levels:
1 = 1,
2 = 2,
3 = 3,
4+ = four or more;
how many people (including yourself)
usually live in your house?
maritala factor with 4 levels:
single = single,
married = married or living with a partner,
separated = separated or divorced,
widowed = widowed.
educan ordered factor with 4 levels:
primary = Primary school,
secondary = High school/secondary school,
polytechnic = Polytechnic or similar,
university = University.
What was the highest level of education you received?
More variables may be added in the future and these may
be placed in any column position. Therefore references
such as xs.nz[, 12] are dangerous.
Also, variable names may change in the future as well as
their format or internal structure,
e.g., factor versus numeric.
The data frame is a subset of the entire data set which was collected from a confidential self-administered questionnaire administered in a large New Zealand workforce observational study conducted during 1992--3. The data were augmented by a second study consisting of retirees. The data can be considered a reasonable representation of the white male New Zealand population in the early 1990s. There were physical, lifestyle and psychological variables that were measured. The psychological variables were headed "Questions about your feelings".
Although some data cleaning was performed and logic checks
conducted, anomalies remain. Some variables, of course,
are subject to a lot of measurement error and bias. It is
conceivable that some participants had poor reading skills!
In particular, the smoking variables contain a small
percentage of conflicting values, and when NAs are taken
into account then there would be several different ways
the data might be cleaned.
If smokeever == 0 then strictly speaking, only
smokepassive is the other variable---the other
smoking variables should either be NA or 0.
MacMahon, S., Norton, R., Jackson, R., Mackie, M. J., Cheng, A., Vander Hoorn, S., Milne, A., McCulloch, A. (1995). Fletcher Challenge-University of Auckland Heart & Health Study: design and baseline findings. New Zealand Medical Journal, 108, 499--502.
chest.nz.