Patient-Reported Outcomes in Pleural Effusions: A Systematic Review.

Pleural effusions cause breathlessness, decreased activity levels, and impaired quality of life. Clinical trials of drainage of pleural effusion use patient-reported outcome measures (PROMs) to assess these variables. This systematic review aimed to identify which PROMs have been used in clinical trials in pleural effusions, what variables were assessed, whether they were responsive to pleural interventions, and whether they have been validated in patients with pleural effusions, including a defined minimal clinically important difference (MCID). A systematic review was performed to identify relevant clinical trials from Medline, EMBASE, Emcare, and CINAHL and data were extracted. From 329 abstracts, 29 clinical trials of pleural effusion drainage that used PROMs as an outcome measure were identified. A total of 16 different PROMs were used. The most used PROMs were unidimensional measurements of breathlessness, particularly the visual analogue scale for dyspnoea (VASD), all of which nearly showed improvements in breathlessness following pleural fluid drainage. Other variables commonly assessed included activity levels and health-related quality of life. Multidimensional PROMs showed inconsistent responsiveness to pleural fluid drainage. Only the VASD was validated in this patient group with a defined MCID. A range of PROMs are used in clinical trials of pleural fluid drainage. No single PROM measures all the outcomes of interest. Unidimensional measurements of breathlessness are responsive to pleural fluid drainage. Only the VASD is validated with an MCID. There is a need for properly validated, response PROMs which measure the key outcomes of interest in this patient group.