Modern Psychometric Measurement and Computerized Adaptive Testing

It is possible to accurately quantify constructs such as nausea, fatigue, and physical functioning using questionnaires referred to as patient-reported outcome measures (PROMs). Modern psychometric techniques ensure that PROMs can deliver exceptionally consistent and accurate measurement and allow for great flexibility in the way that the questions are administered. For example, modern techniques allow two people’s scores to be compared, even if they have answered a different set of questions taken from the full-length questionnaire. This underpins the process of computerized adaptive testing (CAT), in which a computer algorithm can iteratively select the most relevant questions for an individual, based on their previous responses. This chapter introduces modern psychometric theory and computerized adaptive testing and describes how these techniques are revolutionizing quality of life measurement in cancer.