I would acknowledge their concerns, explain the methodology in detail, highlight the reliability and accuracy of the data collection tools, present supporting evidence from multiple sources, and demonstrate the rigorous quality control measures implemented to ensure data integrity.

One way which I have personally experienced is to provide a sample of your data. Depending on the project, you will have to provide sample audio, sample transcriptions along with their corresponding audio segments, the total duration of your recordings, the number of sentences, just to name a few. Once you have finished the project and everything has gotten into place, you can also publish your raw data. This will will be beneficial in two ways: you gain more credibility since everyone will be able to check what your work was based on, and you help other researchers with data that can be used to explore new and different research perspectives.