What are some steps that scientist can take in designing an experiment to avoid false negatives

Hello.

False negative is a condition when you got a negative result that is inncorect.

To prevent false negative occur, first you need to use golden standard test or a test with high specificity.

You can do multiple tests to ensure the specimen is negative and using a positive control to make sure the results are correct.
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They can run the test more than once to confirm their answer(s).

Wetlands form where water and land meet. a lake with a wetland fringe can fill in with decayed plant and animal material to become a wet meadow. a pond can fill in to become a bog or fen. sediment can fill in a river marsh to become a swamp.flooding of coastal lowlands from rising sea levels has created broad coastal marshes that are protected from wave action by barrier islands or reefs. coastal wetlands also form when rivers deposit sediment as they reach the ocean. plants then take root and hold the soil firm against the forces of tides and waves.