The phrase "applied the same methodology" is correct and usable in written English.
You can use it when discussing research, analysis, or processes that utilize a consistent approach or technique across different instances or subjects.
Example: "In our study, we applied the same methodology to ensure that the results were comparable across all test groups."
Alternatives: "utilized the same approach" or "employed the same technique."
When we applied the same methodology to analyzing customer life-cycle economics in several e-commerce sectors including books, apparel, groceries, and consumer electronics we found classic loyalty economics at work.
Due to the preliminary character of this study and the scarcity of reliable experimental anemometric data, we have applied the same methodology already adopted to realise the Italian Wind Atlas.
The researchers applied the same methodology to Obama's 2004 Senate race -- when he did not have Winfrey's endorsement -- to show there was no relationship between Obama votes and her popularity in Illinois, which suggests the two do not merely have crossover appeal.
In our analysis, we applied the same methodology to 22 industry peer groups of public companies.
Oreopoulos (2011) applied the same methodology in Canada, finding a strong and significant preference for English-sounding names and Canadian education and experience with respect to foreign ones.
We have applied the same methodology to analyze the individual scores of closeness centrality and we report the results in Fig. 8.
When we encounter sleeplessness, we apply the same methodology.
Now we apply the same methodology to the men's quarterfinals.
Now, New York City is applying the same methodology to assess one of its programs to prevent homelessness.
We need to apply the same methodology to right-wing terrorists and root out the ideology that inspires them.
This actually marks an improvement: applying the same methodology as the Fawcett Society does in calculating Equal Pay Day shows that, 20 years ago, that gap was 76 days, meaning the date would have fallen almost a month earlier, on 16 October.
