The need to move from descriptive to causal analyses of social change has long been recognized in the social sciences. Due to the difficulties of conducting experimental studies, social scientists use comparisons between countries and over time as fruitful strategies to analyze central processes in modern societies. Comparative research was long constrained by a lack of relevant and reliable data, particularly in the field of social policy where expenditure data often is used. More precise indicators on the institutional design of social policies in areas that are crucial for living conditions and capabilities of citizens are, however, often required, a type of institutional information not easily extracted from official data sources. Instead, a considerable amount of basic research is required concerning both conceptualization and measurement of institutional structures embedded within the welfare state.
