2. Why are patient-reported outcomes important?


Why are patient-reported outcomes important?

Patient-reported outcomes are important because they provide a patient perspective on a disease / treatment that might not be captured by a clinical measurement and yet they may be as important to a patient (and their adherence to the treatment) as a clinical measurement. For example, imagine a scenario in which a patient is diagnosed with chronic obstructive pulmonary disease (COPD). A quick look for a review of clinical studies for treatments of COPD reveals the following:

Tiotropium reduced the number of participants experiencing one or more exacerbations compared with [long-acting beta agonists] (odds ratio (OR) 0.86; 95% confidence interval (CI) 0.79 to 0.93)… There was no statistically significant difference in forced expiratory volume in one second (FEV(1)) or symptom score between tiotropium and LABA-treated participants.

What do these findings say about how the patient felt about the new treatment? What about how they were able to perform their daily activities? Further understanding about what these outcomes mean for the patient is needed. For example:

  • Is an exacerbation something that leads to hospitalisation? Or is it a coughing spell that can be self-managed at home?
  • Is the laboratory test FEV(1) something that directly measures how patients function in different areas of their daily lives?
  • Does the symptom score capture how the patient felt or is it an ‘objective’ measure of symptoms?

Unlike standard clinical outcomes, PROs give us unique insights into how a therapy can affect a patient. Individuals with the exact same health status, diagnosis, or disease may have different perceptions about how they feel and function, as their ability to cope with limitations and disability and other factors can alter perception about satisfaction with life. PRO measures are important as they can lead to medical research that is more focused on real benefits achievable for the patients and of value perceived by them.

The ability to measure well-being as an outcome becomes especially important in clinical situations where the primary goal of treatment is patient well-being rather than prolonging life or reducing disease events. For example, patients diagnosed with a chronic disease that is not immediately life-threatening may be most concerned with their ability to work and live a fulfilling life. A patient with a terminal illness may be more concerned on reducing their pain or on their ability to live longer without major discomfort or suffering.

PROs are essential when externally observable patient-important outcomes are rare or unavailable. PRO assessments can be a primary or a secondary end point in determining treatment efficacy[1]. In some cases, a PRO may be the only feasible end point because there are no markers of disease or treatment activity measurable by a clinician,observer, or laboratory. For example, they may provide the only reasonable strategy for evaluating treatment impact of certain conditions such as pain syndromes, fatigue, disorders like irritable bowel syndrome, sexual dysfunction, and emotional function. PRO instruments are also used to measure adverse events[2] such as nausea and anxiety. This is well established in the field of oncology, where PROs have been used for adverse event reporting with a high degree of patient engagement and compliance (https://ascopubs.org/doi/10.1200/JCO.2007.12.4784). PROs enhance the efficiency and patient-centeredness of clinical documentation and facilitate individualized patient care, a key goal of precision medicine.patient care, a key goal of precision medicine.

[1] The FDA states that if a PRO is being used as a primary or secondary endpoint, its role and the instrument being used to measure it must be clearly defined in the research protocol, with evidence of the PROM instrument’s usefulness from the target population of patients. The CONSORT PRO extension highlights five checklist items recommended for trials in which PROs are primary or important secondary endpoints. An update to the SPIRIT statement (Standard Protocol Items: Recommendations for Interventional Trials), the SPIRIT-PRO Extension provides 16 PRO-specific items for inclusion in clinical trial protocols.

[2] The Patient-Reported Outcomes Safety Event Reporting (PROSPER) Consortium developed guidance for the use of PROs in safety reporting, which outlines definitions and suitable taxonomies, the range of datasets that could be used, data collection mechanisms, and analytic methods