Harmonisation in action
This section outlines some existing and past projects which produced harmonised data in particular research themes.
Harmonisation projects funded by CLOSER
CLOSER funded a set of projects across multiple research themes to produce new harmonised data resources, including guides to cross-study data comparability and cross-study harmonised datasets.
CLOSER has released four datasets of harmonised variables across several CLOSER partner studies on different themes. Each of the CLOSER harmonised datasets is accompanied by a user guide that outlines the process used to harmonise the included variables.
Cross-study data guides
Cross-study data guides summarise the available data on a certain topic across different studies. These guides are often the first step in identifying similar data from multiple studies and may give an indication of the possibility of harmonisation.
CLOSER’s cross-study data guides help researchers explore and compare available measures both within and across multiple CLOSER partner studies. The guides cover dietary data, physical activity data, and cognitive measures.
The projects that created the cross-study data guides for cognitive measures and dietary data carried out extensive scoping on the feasibility of harmonising these measures within and across studies. Follow the links below to read more about the strategies and processes used to determine whether harmonisation was feasible.
Other harmonisation projects
The Harmony tool enables researchers to automate the process of harmonisation using natural language processing. Input items and/or questionnaires and the similarity of the texts is assessed by a neural network.
HALCyon carried out comparable analyses across nine British longitudinal cohort studies, testing the inter-relationships between physical and cognitive capability, social and psychological wellbeing, and underlying biological markers of ageing. This involved retrospectively harmonising secondary data from nine longitudinal cohort studies.
Researchers can access documentation from this harmonisation, including the lists of comparable variables available in each cohort for topics of relevance to HALCyon. The Stata syntax used to clean and recode the data for use in cross-cohort comparisons is also available.
The Gateway to Global Ageing Data is a data and information platform developed to facilitate cross-country analyses on ageing, especially those using the international family of Health and Retirement studies – including the English Longitudinal Study of Ageing (ELSA).
The Measurement Toolkit is a web-based resource to facilitate dietary assessment, anthropometry, and physical activity assessment.
Harmonisation case studies are available for diet, physical activity, and anthropometry, including examples of comparing harmonisation algorithms, network harmonisation, and federated meta-analysis approaches.