Outcomes measures in current Danish pharmacoepidemiological research: a protocol for a systematic mapping review

Abstract

There is a growing interest in complementing the evidence on efficacy and safety of medicinal products gained by randomised clinical trials with real-world data and real-world evidence. Registries provide important sources of real-world data but are typically initiated for administrative purposes. The Danish national registries capture a wide range of information such as health care contacts, social, and economic data; and thereby offer unique possibilities for pharmacoepidemiological research. To gain insight into how registry-based outcome measures from mostly administrative databases are used in real-world evidence studies, the present literature review will investigate the current practice in registry-based studies using Danish health data. A systematic mapping review will be conducted using the literature databases PubMed®/MEDLINE and Scopus®. The search will include Danish registry-based studies aiming at evaluating the effectiveness or safety of medicinal products published from January 1st, 2018 to December 31st, 2019. Data extraction will include the Anatomical Therapeutic Chemical code level 2 of the medicinal product of interest, the outcome measures used, the registry of which the outcome measure has been obtained as well as how the quality of the outcome measure has been considered. The outcome measures extracted will be presented as a categorical overview. These categories will be associated with therapeutic exposure, registry of origin and refereed validation of the outcomes. This systematic mapping review will, as far as we know, be the first of its kind to map outcome measures from Danish national registries used for safety and efficacy studies.

Mapping Outcomes and Registries Used in Current Danish Pharmacoepidemiological Research

“…The present work is, to our knowledge, the first study to systematically map the reported outcomes in pharmacoepidemiological studies across therapeutic areas. 20 This study only builds on studies based on data from Denmark, as we believe that knowledge of the data sources used was important to make the mapping review. However, the rest of the Nordic countries have very comparable registries and access to these are to some extent similar.…”

“…First, the search strategy for PubMed was developed, and based on this, the search strategy for Scopus was developed. Both strategies are available in Table S2 and in the study protocol 20 ( https://doi.org/10.12688/f1000research.52727.1 ), which also explains the conduct of this review in further detail.…”

“…Further specifications are available in the study protocol. 20 Outcomes were herein defined as events or measures identified in registry-based data to evaluate a specified exposure. If the information could not be obtained from the original article text, the supplementary material was investigated.…”

“…As an example, redeemed prescriptions could be assigned to “Prescriptions” if the drug exposure was investigated in relation to prescription of another specific drug (type), or to “Healthcare utilization” if the investigation was related to change in general medication use. The possible outcome subtypes (referred to as “outcome measure subgroups” in the protocol) 20 were defined a-priori to conduct the study based on extracting study-specific outcomes of seven pharmacoepidemiological studies using Danish data. 26–32 The seven studies were semi-randomly selected, ie the studies were randomly selected from a group of 50 studies identified as seemingly relevant during the early development of the search strategy.…”

“…To address this gap in knowledge, the objectives for this study, to our knowledge the first of its kind, were to 1) provide an overview of the different types of outcomes used in recent pharmacoepidemiological studies using Danish registry data to assess drug safety and effectiveness, and the extent of their use, 2) to map these outcomes according to therapeutic level of drug exposure and outcome data source, and 3) to investigate to what extent the studies report on the quality of the applied outcomes. 20 …”