Abstract
Health-related quality of life (QOL) has become an indispensible measure of health. It is an important patient-reported outcome (PRO) endpoint for elective surgery, and is one of the key factors in determining patient priority for elective surgery. In general surgery, there has been a lack of suitable condition-specific QOL instruments to effectively evaluate PRO of elective treatment, examine the current patient prioritization system for elective treatment, and investigate the role of QOL in relation to clinical and other more objective measures of health.
In response to the above, this thesis documents the development, validation, and application of the “Otago Condition-Specific Questionnaire” (OCSQ). The OCSQ is a novel, standardized set of condition-specific QOL instruments tailored for general surgery, and specific for some common elective general surgical conditions, including anorectal conditions, gallstone disease, abdominal wall hernias, varicose veins, and colorectal conditions.
The OCSQ was developed based on an extensive conceptual model of condition-specific QOL, thorough literature review, as well as clinician and patient input. It was validated with rigorous psychometric tests, and was shown to be practical, valid, reliable and responsive.
The QOL information obtained with the OCSQ was correlated against clinical, physiological, and sonographic measures of disease severity in the setting of varicose veins. It was found that QOL related poorly to the objective measures, indicating that QOL is independent of these measures, and can broaden the scope of patient assessment by complementing these measures with a unique facet of information rooted in the patient’s subjective perception.
The OCSQ was used to assess the PRO in a large cohort of patients over a three-year period following elective general surgery. In addition to QOL, the OCSQ was also designed to obtain other PRO information, including patient satisfaction with treatment, patient-perceived treatment-related problems, and duration until return to usual activities after treatment. Overall, PRO was found to be satisfactory. The OCSQ was shown to be valuable in monitoring treatment efficacy, in identifying patients with suboptimal QOL outcome, and in facilitating the comparison of PRO between different conditions and treatments.
The OCSQ was also used to explore how well QOL was represented in the patient’s priority to accessing elective general surgery. It was found that QOL had no bearing on the patient’s priority status. Patients with different levels of QOL had similar priority. The surgeon’s assessment of QOL was not in keeping with the patient’s own view of QOL, and the surgeon did not incorporate his or her assessment of QOL into the final judgement of priority. The OCSQ could help in improving the integrity of patient prioritization by being an integral part of the priority scoring tool, as well as the cognitive feedback package presented to surgeons to enhance their priority scoring performance.