National Health Survey: Health Literacy methodology

Definitions used in the National Health Survey (NHS) and Health Literacy Survey (HLS) are not necessarily identical to those used for similar items in other collections.

A balanced diet, including sufficient fruit and vegetables, reduces a person's risk of developing conditions such as heart disease and diabetes. The National Health and Medical Research Council's (NHMRC) 2013 Australian Dietary Guidelines recommend a minimum number of serves of fruit and vegetables each day, depending on a person's age and sex, to ensure good nutrition and health. Adequacy of intake (consumption) is based on whether a respondent's reported usual daily intake in serves of fruit or vegetables meets or exceeds each recommendation. More information about the guidelines can be found under Usual daily intake of fruit and Usual daily intake of vegetables in this glossary.

The adult literacy and life skills survey (ALLS) was conducted in Australia in 2006 as part of an international study coordinated by Statistics Canada and the Organisation for Economic Co-operation and Development (OECD). The ALLS is designed to identify and measure literacy, numeracy and problem-solving skills. An additional literacy measure, health literacy, was also available.

Alcohol consumption risk levels in the National Health Survey: First Results, 2017-18 (cat. no. 4364.0.55.001) have been assessed using the 2009 National Health and Medical Research Council (NHMRC) guidelines for the consumption of alcohol.

The 2009 lifetime risk guideline (guideline 1) was assessed using average daily consumption of alcohol for persons aged 15 years and over, derived from the type, brand, number and serving sizes of beverages consumed on the three most recent days of the week prior to interview, in conjunction with the total number of days alcohol was consumed in the week prior to interview.

The 2009 single occasion risk guideline (guideline 2) was assessed using questions on the number of times in the last 12 months a person's consumption exceeded specified levels.

The NHMRC drinking guidelines provide two universal guidelines for adults, one for children and young people and one for pregnant and breast feeding women. The following table outlines the risk level for each group. The NHMRC drinking guidelines advise that for anyone under the age of 18, not consuming alcohol is the safest option. However this population group has been assessed in the NHS against the universal guidelines for adults, that is guideline 1 and 2. This allows an assessment of the levels of risky drinking for this age group for both single occasion and lifetime risk.

Alcohol consumption status information was also collected for persons who did not consume any alcohol in the 7 days prior to interview, categorised as:

• Last consumed more than one week to less than 12 months ago;
• Last consumed 12 months or more ago; and
• Never consumed.
   

For more detailed information on the 2009 NHMRC guidelines, see the Australian Guidelines to Reduce Health Risks from Drinking Alcohol

For a detailed explanation of the method used to measure alcohol consumption in ABS health surveys, see Alcohol Consumption in Australia: A Snapshot (cat. no. 4832.0.55.001).

Arthritis is characterised by an inflammation of the joints often resulting in pain, stiffness, disability and deformity.

A chronic disease marked by episodes of wheezing, chest tightness and shortness of breath associated with widespread narrowing of the airways within the lungs and obstruction of airflow. To be current, symptoms of asthma or treatment for asthma must have occurred in the last 12 months.

Accessibility/Remoteness Index of Australia (ARIA) was developed by the Commonwealth Department of Health and Aging (DoHA) and the National Key Centre for Social Applications of Geographic Information Systems (GISCA). ARIA measures the remoteness of a point based on the physical road distance to the nearest Urban Centre in each of five size classes. For more information on how ARIA is defined see Information Paper: ABS Views on Remoteness (cat. no. 1244.0) and Information Paper: Outcomes of ABS Views on Remoteness Consultation, Australia (cat. no. 1244.0.00.001). Also refer to Census Geography Paper 03/01 - ASGC Remoteness Classification - Purpose and Use, available from the ABS website.

The Remoteness Structure for the Australian Standard Geographical Classification (ASGC) 2006 and the Australian Statistical Geography Standard (ASGS) 2016, has 5 categories based on an aggregation of geographical areas which share common characteristics of remoteness, determined in the context of Australia as a whole. The criteria for these categories are based on the Accessibility/Remoteness Index of Australia (ARIA). For more details, see Accessibility/Remoteness Index of Australia definition above and the ASGC page on the ABS website.

The 2014 Guidelines recommend that:

• Adults (18-64 years) should be active most days of the week, accumulate 150 to 300 minutes moderate intensity physical activity or 75 to 150 minutes of vigorous intensity physical activity (or an equivalent combination each week), and do muscle strengthening activities on at least two days each week.
• Older Australians (65 years and over) should accumulate at least 30 minutes of moderate intensity physical activity on most, preferably all, days.
   

For more information, see Australia's Physical Activity and Sedentary Behaviour Guidelines.

See High blood pressure, Diastolic blood pressure and Systolic blood pressure.

Indication of the severity of any bodily pain that the respondent had experienced (from any and all causes) during the last 4 weeks. This is a self-assessment from the SF36 international instrument.

For more information about the SF36, see: 36-Item Short Form Survey (SF-36)

Body Mass Index (BMI) is a simple index of weight-for-height that is commonly used to classify underweight, normal weight, overweight and obesity. It is calculated from height and weight information, using the formula weight (kg) divided by the square of height (m). In the 2017-18 NHS, respondents were also asked to self report their height and weight. To produce a measure of the prevalence of underweight, normal weight, overweight or obesity in adults, BMI values are grouped according to the table below.

Cancer is a condition in which the body's cells grow and spread in an uncontrolled manner. A cancerous cell can arise from almost any cell, and therefore cancer can be found almost anywhere in the body.

These consist of:

• Arthritis;
• Asthma;
• Back problems (dorsopathies);
• Cancer (malignant neoplasms);
• Chronic obstructive pulmonary disease (COPD);
• Diabetes mellitus;
• Heart, stroke and vascular disease;
• Kidney disease;
• Mental and behavioural conditions; and
• Osteoporosis,
   

and are selected for reporting because they are mostly common, pose significant health problems, have been the focus of recent population health surveillance efforts, and action can be taken to prevent their occurrence.

In this publication, persons were included in estimates when they reported that their condition was current and long-term; that is, their condition was current at the time of interview and had lasted, or was expected to last, 6 months or more. In the NHS 2014-15 and 2017-18, estimates also included persons who reported they had diabetes mellitus, angina, heart attack, other ischaemic heart diseases, stroke or other cerebrovascular diseases, but that these conditions were not current and long-term at the time of interview.

Chronic obstructive pulmonary disease (COPD) is a collective term for a group of conditions that include emphysema, chronic bronchitis and chronic asthma that is not fully reversible. Emphysema and chronic bronchitis are the two most common forms of COPD.

Health conditions reported by respondents in the NHS are presented using a classification originally developed for the 2001 NHS by the Family Medicine Research Centre, University of Sydney, in conjunction with the ABS. The classification is based on the 10th revision of the International Classification of Diseases (ICD) and is used for all years from 2001 to 2017-18. See also Long-term health condition.

A current daily smoker is a respondent who reported at the time of interview that they regularly smoked one or more cigarettes, cigars or pipes per day. See also Smoker status.

A chronic condition in which blood glucose levels become too high due to the body producing little or no insulin, or not responding to insulin properly.

Data on diabetes refers to persons who reported having been told by a doctor or nurse that they had diabetes (including persons who were not ever told or not known), irrespective of whether the person considered their diabetes to be current or long-term. This definition was first used for estimates of diabetes in Australian Health Survey: Updated Results, 2011-12 (cat. no. 4364.0.55.003). Estimates of diabetes for all years in the National Health Survey: First Results, 2017-18 (cat. no. 4364.0.55.001), are presented using this definition. In earlier publications prior to National Health Survey: First Results, 2014-15, persons who had reported having diabetes, but that it was not current, were not included.

Measures the pressure in the arteries as the heart relaxes before the next beat. It is the lower number of the blood pressure reading.

A disability or restrictive long-term health condition exists if a limitation, restriction, impairment, disease or disorder has lasted, or is expected to last, for six months or more, which restricts everyday activities.

A disability or restrictive long-term condition is classified by whether or not a person has a specific limitation or restriction. The specific limitation or restriction is further classified by whether the limitation or restriction is a limitation in core activities, or a schooling/employment restriction only.

There are five levels of activity limitation (profound, severe, moderate, mild and school/employment restriction only). These are based on whether a person needs help, has difficulty, or uses aids or equipment with any core activities (mobility, self-care and communication). A person's overall level of core activity limitation is determined by their highest level of limitation in any of these activities.

A grouping of conceptually similar individual questions asked in the Health Literacy Questionnaire (HLQ). 44 questions were grouped into nine domains of health literacy.

Persons who had a job or business, or who undertook work without pay in a family business for a minimum of one hour per week. Includes persons who were absent from a job or business. See also Unemployed and Not in the labour force.

Total household income adjusted by the application of an equivalence scale to facilitate comparison of income levels between households of differing size and composition. The 'modified OECD' equivalence scale is used.

Physical activity (exercise only) which consists of four domains, walking for transport, walking for fitness, sport or recreation, moderate exercise and vigorous exercise, which was undertaken in the last week.

Refers to the composition of the household to which the respondent belongs to. In this publication households are categorised as persons living alone, couple only, couple with child(ren), and other households.

Doctors, nurses, physiotherapists, dieticians and any other health worker survey respondents seek advice or treatment from.

The ability of individuals to gain access to, understand and use information in ways which promote and maintain good health.

A multi-dimensional health literacy assessment tool for surveys, evaluation and service improvement. It focuses on collecting information about the inclusive and equitable access to health information that empowers people to undertake action to improve their own health, as well as the health of their families and communities.

A summary statistic expressed as the mean of the values for each health literacy domain, falling within a range of 1-4 or 1-5 depending on the domain.

Specific lifestyle and related factors impacting on health, including:

• Tobacco smoking;
• Alcohol consumption;
• Exercise;
• Body Mass Index;
• Blood pressure.
   

In the National Health Survey: First Results, 2017-18 (cat. no. 4364.0.55.001), data on heart, stroke and vascular disease refers to persons who reported having been told by a doctor or nurse that they had any of a range of circulatory conditions comprising:

• Ischaemic heart diseases (angina, heart attack and other ischaemic heart diseases);
• Cerebrovascular diseases (stroke and other cerebrovascular diseases);
• Oedema;
• Heart failure; and
• Diseases of the arteries, arterioles and capillaries,
   

and that their condition was current and long-term; that is, their condition was current at the time of interview and had lasted, or was expected to last, 6 months or more.

However, all persons who reported having ischaemic heart diseases cerebrovascular diseases, heart failure and rheumatic heart disease are included, even if they were not reported to be current and long-term at the time of interview. These conditions are automatically considered to be current and long term. Estimates of heart, stroke and vascular disease for 2007-08, 2011-12, 2014-15 and 2017-18 in this publication are presented using this definition. There is limited comparability between 2007-08 and previous years due to a change in derivation methodology in 2007-08.

In the National Health Survey 2017-18, persons aged 18 years and over could consent to having a blood pressure measurement taken at the time of the interview. Participants who recorded a systolic blood pressure reading 140mmHg or greater were counted as having a high blood pressure reading. Note that this only referred to the measurement at the time of the interview and does not necessarily indicate a chronic condition. For this survey, this is distinguished from 'Hypertension' which was self reported as a long term health condition.

For more information, see hypertension.

A household is defined as one or more persons, at least one of whom is at least 15 years of age, usually resident in the same private dwelling. In this survey, only households with at least one adult (aged 18 years and over) were included.

Hypertension (commonly known as high blood pressure) is a condition in which blood pressure in the arteries is elevated, requiring the heart to work harder than normal to circulate blood throughout the body. Hypertension is a major risk factor for hypertensive heart disease, strokes, myocardial infarction (heart attacks) and chronic kidney disease as well as several other medical conditions.

Information on hypertension/high blood pressure was collected in the National Health Survey using two methods. These were:

• a question on whether respondents had ever been told by a doctor or nurse they had any circulatory conditions (including hypertension or high blood pressure), and
• for adults aged 18 years and over, the taking of blood pressure measurements. A person was defined as having high blood pressure if their systolic/diastolic blood pressure was equal to or greater than 140/90 mmHg. Numbers of people with measured high blood pressure do not include people who have high blood pressure but are managing their condition through the use of blood pressure medications.

In the National Health Survey 2017-18, the term 'Hypertension' refers specifically to respondents who had ever been told by a doctor or nurse that they had hypertension or high blood pressure, and does not relate to the voluntary blood pressure measurement.

ICD-10 refers to the tenth revision of the International Classification of Diseases and Health Related Problems. The classification of long-term conditions most commonly used in output from the 2017-18 NHS was developed for use in this survey based on the ICD-10.

This is one of four Socio-Economic Indexes for Areas (SEIFA) compiled by ABS following each Census of Population and Housing. The indexes are compiled from various characteristics of persons resident in particular areas: the Index of Relative Socio-Economic Disadvantage summarises attributes such as low income, low educational attainment, high unemployment and jobs in relatively unskilled occupations. A lower Index of Relative Socio-Economic Disadvantage quintile (e.g. the first quintile) indicates relatively greater disadvantage and a lack of advantage in general. A higher Index of Relative Socio-Economic Disadvantage (e.g. the fifth quintile) indicates a relative lack of disadvantage and greater advantage in general. For further information about the indexes, see Census of Population and Housing: SEIFA, Australia.

A disease of the blood vessels supplying the heart muscle.

Health literacy information collected through individual questions in the Health Literacy Questionnaire (HLQ). For example, "I spend quite a lot of time actively managing my health".

A subset of symptoms including: problems or complaints about the kidneys, renal pain and renal colic (kidney stones).

An Australian standard classification that provides a basis for comparable administrative and statistical data on educational activities and attainment classified by level and field.

A medical condition (illness, injury or disability) which has lasted at least six months, or which the respondent expects to last for six months or more. Some reported conditions were assumed to be long-term, including asthma, arthritis, cancer, osteoporosis, diabetes, sight problems, rheumatic heart disease, heart attack, angina, heart failure and stroke. Diabetes, rheumatic heart disease, heart attack, angina, heart failure and stroke were also assumed to be current.

Margin of Error describes the distance from the population value that the sample estimate is likely to be within, and is specified at a given level of confidence. Confidence levels typically used are 90%, 95% and 99%. For example, at the 95% confidence level the MoE indicates that there are about 19 chances in 20 that the estimate will differ by less than the specified MoE from the population value (the figure obtained if all dwellings had been enumerated). For further information see Technical Note and Data Quality.

Includes organic mental problems, alcohol and drug problems, mood (affective) disorders such as depression, anxiety related problems and other mental and behavioural problems.

Persons who are not employed or unemployed as defined, including persons who:

• Are retired;
• No longer work;
• Do not intend to work in the future;
• Are permanently unable to work; or
• Have never worked and never intend to work.
   

A condition that thins and weakens bone mineral density, generally caused by loss of calcium, which leads to increased risk of fracture.

In this publication, people refers to adults aged 18 years and over.

Refers to exercise only. The 2014 Physical Activity Guidelines are based on Australia’s Physical Activity and Sedentary Behaviour Guidelines.

Derived from the Kessler Psychological Distress Scale (K10). This is a scale of non-specific psychological distress based on 10 questions about negative emotional states in the past 30 days. The K10 is scored from 10 to 50, with higher scores indicating a higher level of distress; low scores indicate a low level of distress. In this publication, scores are grouped as follows:

• Low levels of distress (10-15);
• Moderate levels of distress (16-21);
• High levels of distress (22-29); and
• Very high levels of distress (30-50).
   

A person's general assessment of their own health against a five point scale from excellent through to poor.

To determine whether a difference between two survey estimates is a real difference in the populations to which the estimates relate, or merely the product of different sampling variability, the statistical significance of the difference can be tested. This is particularly useful for interpreting apparent changes in estimates over time. The test is done by calculating the standard error of the difference between two estimates and then dividing the actual difference by the standard error of the difference. If the result is greater than 1.96, there are 19 chances in 20 that there is a real difference in the populations to which the estimates relate. For further information see Data Quality.

Refers to the frequency of smoking of tobacco, including manufactured (packet) cigarettes, roll-your-own cigarettes, cigars and pipes, but excluding chewing tobacco, electronic cigarettes (and similar) and smoking of non-tobacco products. Categorised as:

• Current daily smoker - a respondent who reported at the time of interview that they regularly smoked one or more cigarettes, cigars or pipes per day;
• Current smoker - Other - a respondent who reported at the time of interview that they smoked cigarettes, cigars or pipes, less frequently than daily;
• Ex-smoker - a respondent who reported that they did not currently smoke, but had regularly smoked daily, or had smoked at least 100 cigarettes, or smoked pipes, cigars, etc at least 20 times in their lifetime; and
• Never smoked - a respondent who reported they had never regularly smoked daily, and had smoked less than 100 cigarettes in their lifetime and had smoked pipes, cigars, etc less than 20 times.
   

Four Indexes compiled by the ABS following each population Census. Each index summarises different aspects of the socio-economic condition of areas. The Index of Disadvantage is the SEIFA index most frequently used in health analysis.

The Indexes available for use with 2017-18 NHS data are those compiled from the 2016 Census of Population and Housing. For further information about the indexes, see Census of Population and Housing: SEIFA, Australia.

Measures the pressure in the arteries as the heart pumps blood during each beat. It is the higher number of the blood pressure reading.

Persons aged 15 years and over who were not employed and actively looking for work in the four weeks prior to the survey, and were available to start work in the week prior to the survey.

Refers to the number of serves of fruit (excluding drinks and beverages) usually consumed each day, as reported by the respondent. A serve is approximately 150 grams of fresh fruit or 50 grams of dried fruit. Adequate daily fruit intake refers to whether the respondent met the minimum number of serves as recommended in the NHMRC 2013 Australian Dietary Guidelines. Juices were excluded.

Refers to the number of serves of vegetables (excluding drinks and beverages) usually consumed each day, as reported by the respondent. A serve is approximately half a cup of cooked vegetables (including legumes) or one cup of salad vegetables - equivalent to approximately 75 grams. Adequate daily vegetable intake refers to whether the respondent met the minimum number of serves as recommended in the NHMRC 2013 Australian Dietary Guidelines. Tomatoes were included as vegetables while juices were excluded.