Patient-reported outcome measures in community-acquired pneumonia: a systematic review of application and content validity.

Introduction: Patient-reported outcome measures (PROMs) are a vital component of patient-centred care. Community-acquired pneumonia (CAP) is a significant contributor to morbidity, mortality and health service costs globally, but there is a lack of consensus regarding PROMs for this condition.

Methods: We searched MEDLINE, EMBASE and Cochrane Collaboration for studies, both interventional and observational, of adult recovery from CAP that applied at least one validated PROM instrument and were published before 31 December 2017. The full text of included studies was examined and data collected on study design, PROM instruments applied, constructs examined and the demographic characteristics of the populations measured. For all CAP-specific PROM instruments identified, content validity was assessed using the COnsensus based Standards for selection of health Measurement INstruments guidelines (COSMIN).

Results: Forty-two articles met the inclusion criteria and applied a total of 17 different PROM instruments including five (30%) classified as CAP specific, six (35%) as generic and six (35%) that measured functional performance or were specific to another disease. The 36-Item Short Form Survey (SF-36) was the most commonly used instrument (15 articles). Only one of 11 (9%) patient cohorts assessed using a CAP-specific instrument had a mean age ≥70 years. The CAP-Sym and CAP-BIQ questionnaires had sufficient content validity, though the quality of evidence for all CAP-specific instruments was rated as very low to low.

Discussion: PROM instruments used to measure recovery from CAP are inconsistent in constructs measured and have frequently been developed and validated in highly selective patient samples that are not fully representative of the hospitalised CAP population. The overall content validity of all available CAP-specific instruments is unclear, particularly in the context of elderly hospitalised populations. Based on current evidence, generic health instruments are likely to be of greater value for measuring recovery from CAP in this group.