QCal

Qcal is a an application that was designed in order to calculate the dose and time response curves in insecticide resistance bioassays.

The application uses a logistic regression model to generate values for Lethal Dose / Knockdown Dose (LD/KD) or Lethal Time / Knockdown Time (LT/KT) based on data from a bioassay entered into the Qcal user interface.

The combined language for lethal / knockdown was used because the same mosquito species may exhibit knockdown for some insecticide active ingredients but be killed by others and the active ingredient is not specified in Qcal.

Standard Qcal outputs include values for LD50 / KD50 and LD90 / KD90 or LT50 / KT50 and LT90 / KT90, and Qcal also has an advanced option to obtain values for other custom LD / KD or LT / KT percentages.

The results for the logistic regression model calculations are shown in a graph, and a text box under the graph provides statistical details for the model (Estimate, Standard Error, z–value and p–value) and values for LD50 / KD50 and LD90 / KD90 or LT50 / KT50 and LT90 / KT90 (Log value, Back–transformed value from the log value, Lower Limit for 95% confidence interval and Upper Limit for 95% confidence interval).

Regression model outputs can be saved to an .XLS spreadsheet.