4324.0.55.001 - Microdata: National Health Survey, 2014-15 Quality Declaration 
Latest ISSUE Released at 11:30 AM (CANBERRA TIME) 16/05/2016   
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USING THE TABLEBUILDER

Instructions on how to use the TableBuilder can be found in User Manual: TableBuilder, Jun 2013 (cat. no. 1406.0.55.005) and via the help links within the product itself.

For support in the use of TableBuilder and analysis of the data generated from the TableBuilder, please contact Microdata Access Strategies on 02 6252 7714 or via microdata.access@abs.gov.au.

For confidentiality and/or usability reasons, some data item values have been collapsed and/or restricted for use on the TableBuilder.

As discussed on the File Structure page of this product, this survey is hierarchical in nature. For the TableBuilder, the following structure is in place:

Level 1Level 2Level 3Level 4
Household
|__
Selected Persons
|__
Actions for NHPA Condition Groups
|__
Conditions
|__
Medications
|__
Alcohol - Day consumed
|__
Alcohol - Type consumed


Non-Indigenous Flag

The purpose of the population data item "Non-Indigenous flag" is to assist users in producing non-Indigenous data only. It should not be used to estimate Aboriginal and Torres Strait Islander populations through differencing, as the scope of the National Health Survey excludes Very Remote areas of Australia and discrete Aboriginal and Torres Strait Islander communities.

Note on Continuous Items

Some continuous data items are allocated special codes for certain responses (e.g. 9999 = 'Not applicable'). When creating ranges for such continuous items for use in the TableBuilder, these special codes will NOT be included in these ranges. Any special codes for continuous (summation) data items are listed in the Data Item List (DIL) and will be found in the categorical version of the continuous item. However, note that labelling of '0's in the DIL does not necessarily mean they are excluded from the ranges (for example - identifying 0 as 'Did not visit' or 'Did not do') as they may still be important in some calculations. Reference should be made to the categorical version of the item to identify which codes are specifically excluded. Therefore the total shown only represents 'valid responses' of that continuous data item rather than all responses (including special codes).

For example:

'Systolic blood pressure' is located both in the Selected Persons level folder...
      Graphic: Location of item "Systolic blood pressure" in the Selected Persons level folder

...and the Summation Options.
      Graphic: Location of "Systolic blood pressure" in Summation Options

The following table shows the responses for 'Systolic Blood Pressure' by 'Sex of person'. The continuous values of the data item are contained in the 'A valid response was recorded' row. If the actual continuous values are to be displayed, it is necessary to create a range for them. For information on constructing ranges, see the User Manual: TableBuilder, Jun 2013 (cat. no. 1406.0.55.005).


Graphic: Table of the categorical component of "Systolic blood pressure (mmHG)" by "Sex of person"

Here is the same table with a range applied for the continuous values of 'Systolic blood pressure' (Ranged systolic example). Note that the numbers of respondents for the response 'Not applicable' no longer contribute to the table.


Graphic: Table of ranged continuous component of "Systolic blood pressure (mmHG)" by "Sex of person"

Continuous items can be used to create custom categories in 'My Custom Data' by first ranging the item. For example, creating five year age groupings can be done by ranging the item with a five year increment. However, deviating from groupings of equal increments must be done in 'My Custom Data'. As age is a continuous item, it must first be ranged (for example in one year increments). This ranged item can then be grouped under the 'My Custom Data' tab to form unique age categories. For more information, see the 'My Custom Data' section of the User Manual: TableBuilder, Jun 2013 (cat. no. 1406.0.55.005).

Multi-response data item

Some of the survey's data items allow respondents to provide more than one response. These items are referred to as 'multi–response' data items. When a multi-response data item is tabulated, a person is counted against each response they have provided (e.g. a person may have more than one disability). Therefore, the total for a multi-response data item will be less than or equal to the sum of its components.

The table below shows the number of persons with one or more disability. A person can be counted multiple times, once for each disability they have, with the result that the total does not equal the sum of the contributing cells.

Graphic: Multiple choice table of Disability type


CONFIDENTIALITY FEATURES IN TABLEBUILDER

In accordance with the Census and Statistics Act 1905, all the data in TableBuilder are subjected to a confidentiality process before release. This confidentiality process is undertaken to avoid releasing information that may allow the identification of particular individuals, families, households, dwellings or businesses.

Processes used in TableBuilder to confidentialise records include the following:

  • perturbation of data
  • table suppression.

Perturbation Effects

To minimise the risk of identifying individuals in aggregate statistics, a technique is used to randomly adjust cell values. This technique is called perturbation. Perturbation involves small random adjustments of the statistics and is considered the most satisfactory technique for avoiding the release of identifiable statistics while maximising the range of information that can be released. These adjustments have a negligible impact on the underlying pattern of the statistics.

The introduction of these random adjustments results in tables not summing to totals. While some datasets apply a technique called additivity to give internally consistent results, additivity has not been implemented on this TableBuilder. As a result, randomly adjusted individual cells will be consistent across tables, but the totals in any table will not be the sum of the individual cell values. The size of the difference between summed cells and the relevant total will generally be very small.

Please be aware that the effects of perturbing the data may result in components being larger than their totals. This includes determining proportions.

Table suppression

Some tables generated within TableBuilder may contain a substantial proportion of very low contributors within cells (excluding cells that have counts of zero). When this occurs, all values within the table are suppressed in order to preserve confidentiality. The following error message is displayed at the bottom of the table when table suppression has occurred.

ERROR: The table has been suppressed as it is too sparse
ERROR: table cell values have been suppressed

Weight Variables

Two benchmarked weights are provided with the NHS TableBuilder: ‘Households’ and ‘Selected persons (3)’. ‘Selected persons (3)’ is the default summation, which means that this weight is automatically added to the row of any table. In TableBuilder, these weights can be found under the Summation Options category in the left hand pane. TableBuilder only allows one weight to be used at a time.

When analysing a Household level item, you may want to change the summation weight from selected persons to households - for example, if you wanted to know the number of households in a state, rather than the number of persons living in that state. In this case you would add the weight called ‘Households’ from the Summation Options heading. Similarly, the ‘Selected persons (3)’ weight can be found there as well.

Graphic: Location of Households and Selected persons weights under Summation Options in the left hand pane

Caution should be used when applying the ‘Household’ weight to items from other levels. For example, if the household weight is applied to a selected person level demographic item, such as ‘Sex’, your table will show the number of households with one or more selected persons of that sex. Since up to two people can be selected in the NHS, this will result in some households being counted twice, once for females and once for males.

Graphic: Sex of person weighted using Household weight