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About Data Quality


Health Information

The quality of data collected in the healthcare environment is one of the most important factors in ensuring the care offered to patients is of the highest standard possible.

Whether it is the clinical information a consultant or GP writes in a casenote record or the administrative data entered onto a hospital's computer system by a ward clerk, it is essential that the documented information is as accurate as possible. Failure to collect, report and communicate the correct information can, potentially, have a drastic impact on patient care. Furthermore, accurate and timely data on the activity undertaken in the NHS can be pro-actively used to inform and develop the services it has to offer in line with the healthcare needs of the nation.

Welsh NHS Organisations submit a wide range of data to a number of national databases. The data contained within each is used for a variety of purposes. Most importantly, at a national level it is used to support the management and planning of healthcare and patient services. It is also used in the evaluation of NHS performance trends and, in some cases, is a vital source of epidemiological data.


Data Quality Jigsaw

Data quality can be considered as having six “dimensions” and these dimensions can be visualised as individual pieces of a data quality ‘jigsaw’. Only by fitting all six pieces together and completing the jigsaw can a complete picture of the quality of an organisation’s data be obtained.



The timeliness, completeness, validity, consistency, precision and accuracy of Health Board/Trust data directly affects the reliability of the information used to support these processes. Poor quality data has a significant impact on how the service is managed and affects the quality of care on offer to patients and their families. In the case of some national data sets, the quality of the data also has a direct impact on the reported Health Board/Trust performance against the nationally-agreed targets issued by Welsh Government.


More information on the meaning behind each ‘dimension’ of the data quality jigsaw.