"incidence was calculated" is correct and usable in written English.
For example, "Based on the survey results, the incidence of gender discrimination was calculated."
CI of the annual incidence was calculated using a web-based CI calculator (single incidence rate; Centre for Clinical Research and Biostatistics, the Chinese University of Hong Kong).
For each calendar year between 2004 and 2008, annual incidence was calculated by dividing the number of incident cases by the corresponding annual population at risk.
The TDD incidence was calculated by dividing the total number of incident cases of TDD by the total person-years.
Crude incidence was calculated by dividing the number of cases with incident VTE by the number of person years in the cohorts.
Injury incidence was calculated per 1000 h of training exposure ((∑ number of muscle injuries/∑ h training exposure)×1000).
The incidence was calculated for both the principal item and the secondary item (Figure 2). Figure 2 Morphological variations of IC as observed from the side [18].
Adjusted incidence was calculated where appropriate.
Daily headache incidence was calculated as the proportion of subjects reporting headache out of the total number of subjects.
Age-specific incidence was calculated and extrapolated to estimate national annual influenza pneumonia hospital admissions and in-hospital deaths.
Incidence was calculated for each Project year.
Cumulative incidence was calculated in the presence of competing risks.
