How to Improve Interpretability of Patient-Reported Outcome Measures for Clinical Use: A Perspective on Measuring Abilities and Feelings

Two general classes of concepts measured by patient-reported outcome measures (PROMs) are abilities and feelings. Over the past several decades, there has been a significant progress in measuring both. Nevertheless, current multi-item scales are subject to criticism related to scale length, score dimensionality, interpretability, cultural bias, and insufficient detail in measuring specific domains. To address some of these issues, the author offers an alternative perspective on how questions about abilities and feelings could be formulated. Abilities can be defined in terms of a relationship between the level of performance and the associated perception of difficulty, and represented graphically by an ability curve. For feelings, it may be useful to measure frequency and intensity jointly to determine the proportion of time in each level of intensity. The resultant frequency × intensity matrix can be presented as a bar graph. Empirical data to support the feasibility and validity of these approaches to PROM design are provided, potential advantages and limitations are discussed, and some future research avenues are suggested.