PROMs and quality of care

The impairment of patient’s health is the major driver of healthcare and healthcare research. For many years, the pathophysiological understanding of disease was considered the holy grail of medicine. However, increasingly, the central role of patients is being recognized in current times. Health professionals should treat their patients and not limit their attention to the patient’s disease. Since the patient’s perspective on their disease can only be given by the patient him/herself, this paradigm shift has led to the proliferation and adoption of patient-reported outcomes (PROs) throughout all levels of healthcare. In this chapter we will first introduce a conceptual framework for PROs, according to the World Health Organization definition of health. It will demonstrate how PROs can be and have been developed to assess areas of human functioning across a continuum of social complexity ranging from simple, unidimensional measures of symptoms to complex, integrated domains of social functioning. Generic PROs may intend to provide information that can be used to compare health status between populations. Alternatively, PROs may have a particular focus on specific populations, diseases, or functions. These instruments are called specific instruments. The applications and advantages of specific and generic instruments will be discussed in detail in this chapter. Although the primary application of PROs in rheumatology was traditionally applied as primary or secondary endpoints in clinical trials, they are increasingly used in other measurement settings as well. The chapter includes a description of these developments and the requirements they imply for PROs in detail. Finally the psychometric models that are frequently utilized in the development and evaluation of PROs will be discussed, with particular attention for the modern, item response theory-based approach and how it can be utilized to address difficult-to-resolve measurement-related issues related to the interpretability and reliability of PROs