Best Practices for Longitudinal Data

This paper looks at the growing variety of data sources in research -- e.g., biomarkers -- that are not traditional question-based surveys, and how these can be usefully documented.
This paper proposes best practice for the use of DDI to ensure that there are appropriate metadata to compare data produced across repeated data collection over time.
This paper looks at the unique characteristics of longitudinal data and offers recommendations for structuring metadata in a manner that facilitates analysis over time and metadata reuse.

This paper is intended to provide implementers and those delivering longitudinal data with recommendations on how to use DDI most effectively to support the presentation of longitudinal studies, most commonly on the Web, and to describe best practice for structuring DDI instances.  

Generic Longitudinal Business Process Model
This paper proposes a reference model, the Generic Longitudinal Business Process Model (GLBPM),  for the process of longitudinal data production and use, with an emphasis on the specification and management of the supporting metadata.