172 Chapter 9 In this dissertation, the development, validation, and implementation of the Otology Questionnaire Amsterdam (OQUA) is described. The OQUA is a Patient-Reported Outcome Measure (PROM), a type of questionnaire completed directly by patients to collect information about their health, symptoms, functioning, and quality of life, without interpretation by a physician or other healthcare provider. PROMs play a crucial role in assessing treatment outcomes, monitoring disease progression, and personalizing care based on what matters most to the patient. Selecting the right questionnaire for patients with ear-related complaints has proven to be a difficult and time-consuming task. To facilitate this process, and in the search for a good multiple complaint questionnaire, the first step was to provide a comprehensive overview of existing questionnaires. In Chapter 2 a report on availability of patient reported outcome measures in otology is outlined. A systematic literature search was performed. A total of 155 unique questionnaires addressing any otologic complaint (tinnitus, hearing loss, earache, otorrhoea, and ear-related pressure sensation, vertigo, itch, or dysgeusia) were identified. 33 on tinnitus, 23 on vertigo, 84 on hearing loss questionnaires and 15 multiple complaint questionnaires. Although many ear diseases create multiple symptoms, most of the questionnaires were symptom specific. After performing this mapping review, we decided to start the extensive process of designing and validating a patient reported outcome for patients with one or more ear complaints and the impact of these complaints on the quality of life. Chapter 3 describes the multicentre development of the Otology Questionnaire Amsterdam, abbreviated ‘OQUA’. This cross-sectional study is divided in two phases. In phase 1 in-depth interviews were done to identify relevant types of ear complaints and to formulate items. A pilot study of the first and second draft of the OQUA were part of phase 1 as well. In phase 2 the OQUA was field-tested, and item reduction performed. Explorative factor analysis of the OQUA generated eleven relevant factors. After removal of two factors with low factor loading, nine remained. These nine remaining factors were then labelled: eight factors related to severity and frequency of complaints and one factor related to impact. Both parts of the questionnaire (complaints and impact) can be seen as separate constructs. The complaints-part represents a formative model: items do not necessarily correlate with each other. The impact-part represents a reflective model: a change in the observed variables is caused by a change in the construct. Each item in a reflective model is interchangeable. Factor analysis should only be applied to a reflective model. Hence, item reduction in the complaints-scale was conducted based on expert opinion. In the end the OQUA is a 34-item questionnaire and contains two subscales: complaints and impact of ear complaints on daily life.
RkJQdWJsaXNoZXIy MjY0ODMw