Date—accuracy indicator, code AAA

Identifying and definitional attributes

• Community Services (retired), Standard 30/09/2005
• Disability, Standard 07/10/2014
• Early Childhood, Standard 21/05/2010
• Health, Standard 04/05/2005
• Homelessness, Standard 23/08/2010
• Housing assistance, Standard 23/08/2010

Value domain attributes

Representational attributes

Collection and usage attributes

Any combination of the values A, E, U representing the corresponding level of accuracy of each date component of the reported date.

This data element consists of a combination of three codes, each of which denotes the accuracy of one date component:

A – the referred date component is accurate

E – the referred date component is not known but is estimated

U – the referred date component is not known and not estimated.

This data element contains positional fields (DMY) that reflects the order of the date components in the format (DDMMYYYY) of the reported date:

Field 1 (D) – refers to the accuracy of the day component;

Field 2 (M) – refers to the accuracy of the month component;

Field 3 (Y) – refers to the accuracy of the year component.

This data element is valid only for use with dates that are reported/exchanged in the format (DDMMYYYY).

Example 1: If a date has been sourced from a reliable source and is known as accurate then the Date accuracy indicator should be informed as (AAA).

Example 2: If only the age of the person is known and there is no certainty of the accuracy of this, then the Date accuracy indicator should be informed as (UUE). That is the day and month are “unknown” and the year is “estimated”.

Example 3: If a person was brought in unconscious to an emergency department of a hospital and the only information available was from a relative who was certain of the age and the birthday’s 'month' then the Date accuracy indicator should be informed as (UAA). A year derived from an accurate month and accurate age is always an accurate year.

The Date accuracy indicator can be useful for operational purposes to indicate the level of accuracy of a date that has been collected at any point in time. It can indicate whether the stored date needs to be followed up until it reaches the intended minimal required accuracy. For example, if a person was brought in unconscious to an emergency department of a hospital the level of accuracy of the date collected at that point may not be satisfactory. It is likely that the correct date of birth can be obtained at a later date. The Date accuracy indicator provides information on the accuracy of the entered dates that may require further action.

For future users of the data, it may also be essential to know the accuracy of the date components of a reported date.  

Data element attributes

Collection and usage attributes

Collection constraints:

If constraints for the collection of the date are imposed, such as ‘a valid date must be input in an information system for unknown date components’, the Date accuracy indicator should be used along with the date as a way of avoiding the contamination of the valid dates with the same value on the respective date components.

Example:

Some jurisdictions use 0107YYYY and some use 0101YYYY when only the year is known. When month and year are known some use the 15th day as the date i.e. 15MMYYYY. Where this occurs in a data collection that is used for reporting or analysis purposes there will be dates in the collection with the attributes 0107YYYY etc., that are accurate and some that are not accurate. Without a corresponding flag to determine this accuracy the analysis or report will be contaminated by those estimated dates.

Provision of a date is often a mandatory requirement in data collections.

Most computer systems require a valid date to be recorded in a date field i.e. the month part must be an integer between 1 and 12, the day part must be an integer between 1 and 31 with rules about the months with less than 31 days, and the year part should include the century. Also in many systems, significant dates (e.g. date of birth) are mandatory requirements.

However, in actual practice, the date or date components are often not known (e.g. date of birth, date of injury) but, as stated above, computer systems require a valid date. This means that a date MUST be included and it MUST follow the rules for a valid date. It therefore follows that, while such a date will contain valid values according to the rules for a date, the date is in fact an ‘unknown’ or ‘estimated’ date. For future users of the data, it is essential to know that a date is accurate, unknown or estimated and which components of the date are accurate, unknown or estimated.

Source and reference attributes

Standards Australia

Standards Australia 2002. AS5017—2002 Health Care Client Identification. Sydney: Standards Australia

Relational attributes