The Consumer Product Safety Commission said that they didn't find home test kits useful for detecting lead because in their test, they found too many false negatives and a few false positive test results.

NPR: Do Home Lead-Testing Kits Work?

For 50 years, the Pap test has been the gold standard for detecting cervical cancer.

CNN: Pap test challenged by HPV DNA test

So we sort of focused our recommendations on, you know, the Lead Check Test and something called the Lead Inspector, which had more ability for detecting lead in pink or red objects, which can sometimes fool your test results.

NPR: Do Home Lead-Testing Kits Work?

Though its accuracy at detecting precancerous conditions is far from established, the test has proven beneficial for some patients.

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