Estimating the Growth Rate and Doubling Time for Short-Term Prediction and Monitoring Trend During the COVID-19 Pandemic with a SAS Macro

Stanley Xu; Christina Clarke; Susan Shetterly; Komal Narwaney

is the (which was not peer-reviewed) The copyright holder for this preprint . https://doi.org/10.1101/2020.04.08.20057943 doi: medRxiv preprint corresponding number of deaths will also be used.; /*First, get the number of deaths/events on the last day (k) of the last period for estimating the growth rate*/ proc sql noprint; select distinct &numevents into :y_k from &indat where &dateofevent = &fup_end ; quit; /*Next, get r_k from the doubling time, which is the estimated growth rate from the last period*/ proc sql noprint; select distinct r ,r_lowerCL ,r_upperCL into :r_k, :r_k_lower, :r_k_upper from r_doubling_time where end_day = &fup_end ; quit; %put &fup_end &y_k &r_k &r_k_lower &r_k_upper; data prediction; k=&fup_end; do i=1 to &int_length; m = k + i; y_m = round(&y_k*((1+&r_k))**(m-k)); y_m_lowerCL = round(&y_k*((1+&r_k_lower))**(m-k)); y_m_upperCL = round(&y_k*((1+&r_k_upper))**(m-k)); output; end; format m date9.; keep m y_m y_m_lowerCL y_m_upperCL; run;