Comparing the use of patient-reported outcomes in clinical studies in Europe in 2008 and 2018: a literature review

PURPOSE: Several guidelines for the use of patient-reported outcomes (PROs) in clinical studies have been published in the past decade. This review primarily aimed to compare the number and compliance with selected PRO-specific criteria for reporting of clinical studies in Europe using PROs published in 2008 and 2018. Secondarily, to describe the study designs, PRO instruments used, patient groups studied, and countries where the clinical studies were conducted. METHODS: A literature search was conducted in MEDLINE to identify eligible publications. To assess the number of publications, all abstracts were screened for eligibility by pairs of reviewers. Compliance with PRO-specific criteria and other key characteristics was assessed in a random sample of 150 eligible full-text publications from each year. Randomized controlled trials (RCTs) were assessed according to the full CONSORT-PRO checklist. RESULTS: The search identified 1692 publications in 2008 and 4290 in 2018. After screening of abstracts, 1240 from 2008 and 2869 from 2018 were clinical studies using PROs. By full-text review, the proportion of studies discussing PRO-specific limitations and implications was higher in 2018 than in 2008, but there were no differences in the other selected PRO-specific criteria. In 2018, a higher proportion of studies were longitudinal/cohort studies, included ≥ 300 patients, and used electronic administration of PRO than in 2008. The most common patient groups studied were those with cancer or diseases of the musculoskeletal system or connective tissue. CONCLUSION: The number of clinical studies from Europe using PROs was higher in 2018 than in 2008, but there was little difference in compliance with the PRO-specific criteria. The studies varied in terms of study design and PRO instruments used in both publication years. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s11136-021-02946-7.