Every single survey on human trafficking is designed to produce false positives. One-third of the trafficking victims identified by the ILO estimate are women and men in arranged marriages.
https://www.ilo.org/wcmsp5/groups/public/@ed_norm/@ipec/documents/publication/wcms_586127.pdf

But wait it gets worse. The way researchers collect this data is bananas. First, they only carry out surveys in countries where they're likely to find forced marriages.

Second, they don't just ask respondents about their own experiences. They also ask whether children, parents or siblings have been in forced marriages. This results in double-counting and makes it harder to assess whether they consented to the marriage .

Third, and this is NUTS, the researchers treat any refusal to answer a question as evidence of forced marriage!

Any defensible survey methodology would include a separate category for "refused to answer." The ILO treats those as evidence of trafficking!

The *only* reason to make these choices is to get the numbers as high as possible. These extremely important caveats appear in a separate document from the main findings in the detailed methodology section. Page 74. Unbelievable.