Statistical methods
All statistical methods are documented in the source code, which is publicly available. https://github.com/shapiromatron/hawc. If you're interested in locating a particular method and have troubles navigating the source code, please contact us and we can help.
Bioassay
 For single doseresponse confidence intervals displayed on the doseresponse plot:
 For continuous data, 95% confidence intervals are calculated using a twotailed ttest (eg., https://hawcproject.org/ani/endpoint/1/)

For dichotomous data, intervals are calculated using the inverse standard normal cumulative distribution function evaluated at \(1\alpha/2\), using a twosided 95% confidence interval (eg., https://hawcproject.org/ani/endpoint/30/)

For calculating percent control relative to the control response (in datapivot, eg., https://hawcproject.org/summary/datapivot/assessment/1/featureexamplepercentdifference/):
 95% confidence intervals are calculated using a Fisher Information Matrix, assuming independent normal distributions
 This statistic assumes that first dosegroup is control, and all other dosegroups are compared to control
 Calculation of confidence intervals requires the following:
 The endpoint dataset must provide variance measures (i.e. standard deviation or standard error)
 The control mean value must not be equal to zero (cannot divide by zero)
 The n for each dosegroup must be provided, including control
 A detailed description is available: CI description
Invitro
 For single doseresponse confidence intervals displayed on the doseresponse plot:

same as continuous methods for bioassay data, as described above

For calculating percent control relative to the control response (in datapivot):
 same as methods for bioassay data, as described above
Epidemiology (v1)

For confidence intervals on epidemiology resultdatasets
 If 95% confidence intervals are entered, they are presented (eg., https://hawcproject.org/epi/result/98/)
 If 95% confidence intervals are not entered, and the response is a normal distribution with a SD or SE:
 95% confidence intervals are calculated using a twotailed ttest (eg., https://hawcproject.org/epi/result/1445/)

For calculating percent control relative to the control response (in datapivot):
 same as methods for bioassay data, as described above
 The control group is determined by the following rules:
 If 0 groups are marked control (using comparisonset groups), the first group will be chosen as control
 If 1 groups is marked control (using comparisonset groups), the first group will be chosen as control
 If ≥ 2 groups are marked control (using comparisonset groups), a random control group will be chosen for control for all calculations