Application of Mixed-Method Study Designs in Health- Economic- Related Studies. A Narrative Review

Mixed method studies aim at combining qualitative and quantitative research methods and thereby trying to offer deeper insights into a study topic. The German Institute for Quality and Efficiency in Health Care (IQWiG) recommends to combine qualitative and quantitative data to generate a wider spectrum of information for evaluation of health care services. This review aims to give an overview over mixed method designs used in health care research studies published over the last five years. A narrative database search was conducted in Pubmed. According to pre-defined inclusion and exclusion criteria, titles and abstracts were screened regarding research location and mixed method designs and research methods. In a second step, full-text screening was used to extract details. In total n=236 research papers were identified. For full text screening n=82 studies remained and were included in the analysis. 25% of the evaluated studies (n=21) came from the UK, only n=3 relevant studies were conducted in Germany. The three main research fields were public health (n=27), followed by prevention & promotion (n=22) and health policy (n=16). 4 out of 82 studies focused on economic evaluations only. N=54 studies applied a data triangulation design. The majority of the studies used quantitative primary data collection as main research method (n=43). Qualitative interviews as an add-on methodology were used most frequently (n=29). Costs or socioeconomic factors were addressed in questionnaires or interviews in n=43 studies. Cost-analysis were integrated in n=12 studies as an add-on method. Of the evaluated studies, mixed method study designs are not often applied in health economic evaluations or studies with economic focus as of today. Further research is warranted on the reasons for this finding as it is unclear whether this is due to a lack of methodological knowledge or other influencing factors.