Erstellung eines evidenzbasierten Bewertungs- und Informationssystems für OTC-Arzneimittel

Self-medication with over-the-counter (OTC) drugs is of great importance in Germany. About 50 % of the medication dispensed in community pharmacies are non-prescription drugs which are available for self-medication. Self-medication provides a variety of benefits to patients, pharmacists and the society as a whole. In order to ensure a safe and effective therapy, counselling on OTC drugs by pharmacists is essential. Furthermore, evidence-based knowledge is becoming increasingly important for adequate advice and counselling. However, the field of self-medication has so far been almost neglected in terms of evidence-based principles. In community pharmacies, there is often not enough time during day-to-day work to perform an extensive literature research or an evidence-based evaluation of OTC drugs. Despite the need for supporting evidence-based choices of OTC drugs, an applicable tool or available scientific analysis regarding self-medication does not yet exist. Thus, the aim of this project was to develop an applicable evaluation and information system based on the structured analysis of data from clinical studies for supporting evidence-based counselling on self-medication. Due to the treatment of migraine headaches being highly relevant to current practice, this indication was selected in order to aid in the development of the system. The Analytic Hierarchy Process (AHP) was used for creating and structuring the evaluation system as this method supports complex decision-making problems. The problems associated with decision-making were structured in a hierarchy by defining the overall goal (an effective and well-tolerated migraine therapy), the relevant criteria (efficacy and tolerability endpoints) and the available alternatives (OTC drugs). The OTC drugs were rated according to each criterion. Finally, the overall results for the OTC drugs were calculated taking into consideration the relative weight of each criterion. Expert and patient perspectives were incorporated for criteria selection and the weighting process. For assessing the OTC drugs with respect to the single criteria or endpoints, a systematic evidence-based procedure was applied. Initially, a systematic literature research was conducted for each OTC drug. Studies were selected according to pre-defined inclusion criteria and efficacy and tolerability data were analysed. In addition to determining effect estimates, quality of the evidence was evaluated by applying the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system. The results of the evaluations of the OTC drugs were finally summarized in transparent and easily accessible Summary of Findings (SoF) tables, thereby providing the basis of the information system. The evaluation system provides a clear structure for a therapeutic application by presenting all evaluation results of the various OTC drugs according to efficacy and tolerability aspects. It facilitates weighing up the advantages and disadvantages of a therapy and enables the comparison of evaluated OTC drugs. Moreover, it can be flexibly adapted to different OTC applications. The relative importance of the efficacy and tolerability criteria can be adjusted according to individual patient preferences. Thus, the patient can be actively involved in the decision process and individual preferences are taken into account when selecting OTC drugs. The information system provides a high level of transparency. SoF tables of OTC drugs present detailed study data in a scientifically processed way. Thereby, a structured and transparent presentation of evidence-based data and information was achieved, enabling the evaluation results to be retraced. On the one hand, SoF tables offer fast availability of underlying data, on the other hand, further research can be conducted on the basis of the deposited information. Additionally, quality evaluations of the evidence were included which is essential in order to prevent biased results. According to GRADE, quality reflects the confidence in the estimate of effect, therefore it provides important information for a correct interpretation of the effect estimate or result. Information on effect size and quality of evidence were visualised by traffic light labelling which supports an easy orientation. Regarding the final results for migraine therapy, it was found that the analysed OTC drugs are effective and well-tolerated when used short-term within self-medication of acute migraine headaches. A web-based tool was used for providing the results. In this way, practical rele-vance and applicability in community pharmacies could be increased. The web-based implementation of the evaluation and information system allows an easy and quick access for the use in daily practice. In this thesis, an evidence-based and practical evaluation and information system was developed which, for the first time, combines the different demands of scientific clarity and transparency. The developed system provides evidence-based data as well as transparent and reproducible results of the efficacy and tolerability evaluations of different drugs applied for self-medicating acute migraine headaches. After the inclusion of further areas of self-medication, the web-based application will be a meaningful support for evidence-based counselling on OTC drugs in community pharmacies. The evaluation and information system will facilitate combining evidence-based knowledge with the pharmacist’s clinical expertise and the individual patient’s preferences in the daily routine.