eprintid: 35102
rev_number: 12
eprint_status: archive
userid: 8279
dir: disk0/00/03/51/02
datestamp: 2024-09-20 09:22:33
lastmod: 2024-09-20 09:23:07
status_changed: 2024-09-20 09:22:33
type: doctoralThesis
metadata_visibility: show
creators_name: Rochon, Justine
title: Impact of Institutional Research Activity on Quality of Care and Patient Outcome in Ovarian Cancer
divisions: i-911800
adv_faculty: af-05
abstract: Randomized controlled trials are considered the gold standard for the development and approval of new treatments in evidence-based medicine. The effects of individual participation in clinical research have been discussed in the literature for decades, particularly in the field of oncology. The present thesis investigated whether institutional participation in clinical trials has an influence on the quality of care and how this affects treatment outcomes in patients with ovarian cancer, regardless of whether the patients participate in clinical trials or not. The focus of the thesis was on exploring the underlying mechanisms in Donabedian's triad of health care with structure, process, and outcome as a conceptual framework, while taking into account methodological challenges of observational studies. The thesis used data from three cohorts of a German quality assurance program for ovarian cancer. The hypothesis was that institutional research activity is associated with better adherence to treatment guidelines for ovarian cancer and that this, in turn, leads to better treatment outcomes for the affected patients. Surgical standards and guideline-based administration of chemotherapy were assumed as potential mediators between hospital-related participation in clinical trials and overall survival of patients. In the study, a new method for causal mediation analysis was introduced and further developed for various scenarios and types of variables, enabling the investigation of direct and indirect effects of institutional research activity on patient survival, i.e., a time-to-event outcome with censoring. This made it possible for the very first time in this context to examine and quantify causal pathways between structural characteristics of the treating institution, process variables reflecting treatment quality, and patient-relevant outcomes such as survival. This also allowed for the practical embedding of Donabedian's quality model and the integration of its three components (structure, process, and
outcome) into a single analysis model. In addition, patient and disease characteristics could be taken into account. The problem of clustering was solved by bootstrap techniques. The study showed heterogeneity in the treatment of ovarian cancer in Germany and identified opportunities for improvement. It turned out that hospitals participating in clinical trials provided better care, at least in the first cohort, and thus achieved longer overall survival for their patients. In later cohorts, however, this effect was no longer observed. Therefore, the dissertation concluded that the question of whether participation in clinical trials improves the outcome in patients with cancer diagnosis remains highly relevant but controversial. Adherence to treatment guidelines for ovarian cancer improved over time. Surprisingly, this improvement in treatment quality did not translate into even longer survival for the affected patients. Future efforts in this area should therefore be aimed at translating new findings from clinical research into daily practice in a timely manner, but also at further examining influencing variables on treatment success in order to ensure the best possible care for patients with ovarian cancer while at the same time achieving longer overall survival. For the investigation of the underlying mechanisms of action, causal mediation analyses should be used.
date: 2024
id_scheme: DOI
id_number: 10.11588/heidok.00035102
own_urn: urn:nbn:de:bsz:16-heidok-351028
date_accepted: 2024-07-15
advisor: HASH(0x55de57b21c80)
language: eng
bibsort: ROCHONJUSTIMPACTOFIN20240715
full_text_status: public
place_of_pub: Heidelberg
citation:   Rochon, Justine  (2024) Impact of Institutional Research Activity on Quality of Care and Patient Outcome in Ovarian Cancer.  [Dissertation]     
document_url: https://archiv.ub.uni-heidelberg.de/volltextserver/35102/1/Rochon_Justine_05_10_1975_Dissertation.pdf