Erschienen:
[Erscheinungsort nicht ermittelbar]: [Verlag nicht ermittelbar], 2016
Sprache:
Englisch
Identifikator:
Entstehung:
Hochschulschrift:
Dissertation, 2016
Anmerkungen:
Beschreibung:
Placebo controlled randomised clinical trials are the gold standard for testing the efficacy of new pharmaceutical compounds. After these studies are completed and the product is assessed by the responsible authorities, only a fraction of the trials are published while the data can be a rich source for evidence based medicine. In this thesis, we demonstrate that analyses on raw study data from drug registration trials can answer a variety of research questions related to some of the current challenges in schizophrenia research, subsequently aiding decision making in regulatory and clinical practise. We found considerable publication bias and selective publication of placebo controlled clinical trials performed with insomnia medications, with positive trials being more likely to be published. This highlights the need to obtain access to raw study data. With respect to the current challenges in schizophrenia research, we found that the magnitude of the effect of atypical antipsychotics was smaller in studies conducted in North America compared to studies conducted in the EU and the rest of the World. As the difference was not statistically significant, extrapolation of results across regions could be possible. We also found that the change in diagnostic criteria over time (from DSM-IV to DSM-5) does not drastically change the diagnosed patient population, demonstrating that results of previous clinical trials in schizophrenia are valid for the current patient population. Finally, we found that atypical antipsychotics improve insight in schizophrenia, and that this improvement is associated with improvements in other symptoms.