Why might qualitative secondary sources sometimes be considered low in reliability?

Qualitative secondary sources may be considered low in reliability primarily because they are prone to interpretation bias. This means that the way in which researchers interpret and analyze qualitative data can be influenced by their own perspectives, experiences, and biases. Unlike quantitative data, which relies on numerical analysis and statistical validity, qualitative data often involves subjective interpretations, making it susceptible to variations in how different researchers might understand and present the findings. This inherent subjectivity can lead to inconsistencies and limit the reliability of the conclusions drawn from such sources, especially when they don't follow rigorous methodological standards.

In contrast, while depth can be an important aspect of qualitative research, a lack of depth does not inherently define the reliability of the sources. The volume of data or the need for replication does not directly address the reliability of interpretation, as qualitative research does not always lend itself well to replication in the same way quantitative research does. Thus, the focus on interpretation bias as a concern helps clarify why qualitative secondary sources are often viewed as having lower reliability.