However, case studies can prove to be valuable for scientists as they provide in depth analysis, which takes into consideration multiple variables. The issue that often comes from breadth studies is that many people have different opinions. For example, the true meaning of democracy is often debated and interpreted differently by various parties. This is a problem often exacerbated by the fact that many countries have different political cultures. Dogan (1994:36) argues that mass data may have ‘lured some researchers into a false sense of security’ and therefore prevented them from assessing the ‘validity of quantitative data’ (Dogan, 1994:41).
Quantitative research is often conducted on the basis of generally acknowledged and accepted mass data. Some of these worldwide studies, which come from sources such as the World Values Survey, use statistics from specific institutions such as the United Nations, World Bank and the European Union. These do not always necessarily provide a completely accurate picture of each country.
For example, political participation in Islamic countries has a different face to that of the Western world due to the belief that different genders must fulfill certain roles (Norris and Inglehart, 2004). However, researchers don’t have the resources to conduct all of their own studies, and even if they did so, by the time they had conducted the studies, the economic and social realities may have changed. Landman (2000) states that “single-country studies provide contextual description, develop new classifications, generate hypotheses, confirm and inform theories, and explain the presence of deviant countries identified through cross-national comparison.” This is why case studies can often be a useful analytical tool. This is portrayed in Robert Putnam’s Making Democracy Work whereby he analysed 20 different regions throughout Italy across 20 years of study.
The study was conducted to assess how difference in institutional reform impacts institutional performance. When he came across disparities in regional findings, he assessed the reasons for cross-temporal and cross-sectional variation in institutional performance, and he conducted an in-depth focus of six particular regions. This would not have been possible with a large-N study.
As Bryman (1974) notes, “qualitative research offers flexibility in design and application which are more sensitive to the complexities of social phenomena than quantitative methods”. George and Bennett (2005) agree, arguing that a key benefit of case studies is that you can utilise process-tracing to explain outcomes even with limited resources. However, comparative politics as a whole does not sacrifice breadth for depth as case studies mean that only one entity is analysed and are therefore of a limited value to political scientists.
Case studies merely lay foundations as an explorative method to further understanding quantitative analysis (Lijphart,1975:160) as they are only useful to “disconfirm a regularity to a limited degree” (Sartori, 1994:23). Therefore, in the field of comparative politics they have limited value, as generalisations cannot be drawn from them.