A system of metadata to control the process of query, aggregating, cleaning and analysing large datasets of primary care data

Using routinely collected data to evaluate a leaflet campaign to increase the presentation of people with memory problems to general practice: a locality based controlled study

“…21 This involved creating a large, single data table, with controlled metadata headers for each column of data and one line per patient. 22 The individual patient's identity is pseudonymised -replaced by a unique number which can only be decoded within the originating practice. These data were transferred into a statistical package for analysis (SPSS version 15).…”

Building a Pan-Canadian Primary Care Sentinel Surveillance Network: Initial Development and Moving Forward

“…Although these codes lack the specificity preferred for primary care, this is the current coding standard for many EMRs in Canada and will be a potential limitation for the initial data extraction process. The development of metadata and data processes is explained more fully by van Vlyman and de Lusignan 18 in their discussion about a defined number of named elements that convey meaning, given that medical data are complex to process. Access to diagnostic procedures (eg, spirometry) or referrals (eg, referral to psychiatrist) will not be available in all EMRs and will be detailed, as applicable, for each practice site.…”

Defining datasets and creating data dictionaries for quality improvement and research in chronic disease using routinely collected data: an ontology-driven approach

“…21 However, this was developed when we were principally working with just primary care data and complex methods are needed to cope with linking heterogeneous datasets. We have subsequently developed and added a solution-orientated taxonomy to report data extraction errors, so we can understand any gaps in our data.…”