OBJECTIVES:

Enriched observational studies that combine primary data collected from investigating sites with secondary administrative claims data offer multiple advantages. Primary data collection allows to identify patients with certain conditions that are not otherwise identifiable in existing claims data, due to their intrinsic limitations. On the other hand, access to existing data sources allows to reduce primary data collection burden, focus on critical information detected in routine care, and optimize study timelines. Here, we describe the implementation of a rigorous enriched study design in Italy.

METHODS:

The proposed framework is based on the following principles: (1) the design of a unique protocol with both a cross-sectional or prospective cohort study and the retrospective administrative data; (2) the recruitment of both the investigating sites and the Local Health Authorities (LHAs), i.e. the subregional institutions that collect administrative claims data, whose catchment area includes the patients identified in investigating sites; (3) a strict collaboration between the investigating site and its LHA for linking secondary and primary data; (4) the design of a unique patient consent informing on the request to access both primary and secondary data; (5) a single ethics application process for both the investigating site and its LHA.

RESULTS:

Through this integrated approach we perform exact data linkage between the different data sources and avoid the potential bias of probabilistic linkage. Currently, ethics approval processes are ongoing for studies with this design in Italy.

CONCLUSIONS:

This framework outlines valuable methodological indications to effectively design an enriched study in the fragmented nature of the Italian healthcare system. A strong coordination and standard operating procedures are needed for ensuring high quality in data handling and integration, as well as appropriate analytic methods to mitigate bias and correctly interpret results, maximizing the value of observational studies.