Answer: The results are considered more reliable because they were documented by separate investigations.
Step-by-step explanation:
Scientific investigation can be define as the fact finding inquiry which uses a particular scientific methodology (observation, making hypothesis, testing hypothesis on the basis of experiments, analysis of the data and conclusion) to answer questions related to the cause of natural events and processes occurring in the universe.
If same investigation done by many scientists and if they obtain similar results this increases the reliability and validity of the methodology and approach used to answer the query of the investigation.