BackgroundQuality of dental epidemiology data is dependent upon common understanding of what is required, collection of data in line with guidance and correction of incomplete or missing data. Action has been taken in Wales to ensure common understanding, require data collection in line with guidance and provide feedback on performance.

MethodInformal discussion about and audit of the epidemiology process clarified the roles of staff involved in dental surveys. Changes were made to the survey protocol, training and calibration exercise, data collection format and process, data verification and cleaning processes. Some changes were intended to improve understanding of what is required. Feedback on performance is provided. Some data fields are mandatory. Data collection staff are encouraged to check data.

ResultsBetween 1998 and 2000 postcode entry improved in all health authorities. Recognition by a postcode look-up file improved by 20% in one health authority (Figure 1). For the survey of 5 year olds which took place in 1999-2000 approximately 300 records had to be removed from one health authority’s data set because subjects not been seen. There were no such anomalies in the survey of 12-year-olds 2000-2001. In the 1999-2000 survey of 5-year-olds 7% of children had their age incorrectly recorded. There were no anomalous entries for age for the survey of 12-year-olds that took place in 2000/2001 (Figure 2).

Improving the Quality of Dental Data

Monaghan NP, 1Morgan MZ, 2

1 Directorate of Public Health, Bro Taf Health Authority2 Dental School, University of Wales College of Medicine

AcknowledgementsThe support of the National Assembly for Wales is acknowledged gratefully in the funding of the Welsh Oral Health Information Unit and of the Dental Epidemiology and Training Exercises.

Figure 1: Changes in postcode recognition rates, for surveys of 14 year old children 1998/99 and for 12 year old children 2000/2001.

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Figure 2: Changes in recorded inaccuracies in age, for surveys of 5 year old children 1999/2000 and for 12 year old children 2000/2001.

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ConclusionsClear guidance, use of mandatory fields, encouraging staff to correct data at time of entry and providing feedback to staff has increased the quality of the dental epidemiology data collected in Wales.