Condition to Run Macro based on Cell Value

I'm trying to come up with an IF statement that will trigger my macro to run based on a specific value in one cell. My Spreadsheet has many tabs. This is for a forecasting template.

Here is what I have come up with but I am running out of ideas..

function Sum_Calcs() {
   var spreadsheet = SpreadsheetApp.getActive();
   spreadsheet.setActiveSheet(spreadsheet.getSheetByName('Integrity Check'), true);
   spreadsheet.getRange(K20).getValue(getActiveRange(), true);

if(activeRange === "1") {
}

//My Script is then located beneath//

Any help is much appreciated!