It wasn't: even the original book cited so few sources that its methodology was roundly criticized.
However, the methodology used in the initial epidemiological studies has been criticized.
The methodology and conclusions of the study have been criticized by teachers' unions.
Frale's methodology has been criticized, partly based on the objection that the writings are too faint to see.
The study initially found very favorable results for coiling, however its results and methodology were criticized.
His methodology and the statistical analysis have been criticized by mathematicians.
His methodology was criticized for providing no conclusive evidence for the existence of past lives.
However, the methodology of the these studies has been criticized.
The sample size, controls, and methodology of that study were criticized.
The methodology of the authors has been criticized.