"You really know which is the negative control sample?"
Acute tests are not valid if mortality in the control sample is greater than 10%.
Chronic tests are not considered valid if mortality in the control sample is greater than 20%.
Early life stage tests are not considered valid if mortality in the control sample is greater than 30%.
I haven't even given you a control sample from Daniel Stone yet.
This study has been criticized as the study's control sample of Herskovitz (1930) was not considered representative.
For example, the victim's own blood and hair constitutes a control sample.
The scheme was evaluated using a matched control sample of cases from adjacent areas.
Because the control sample of people still at home at second assessment was so small, no conclusions are possible.
Finally, Bittner et al. did not include the seven control samples in their analysis.