key/value find/filter instead of looping object [duplicate]

Is there a way to find key/value instead of looping through the itemList? The below code works but it does not look like this code is optimized, is there a better way to do than this ?

for (var i = 0; i < this.itemList.length; i++) {
    if(this.itemList[i].type){
      if (this.itemList[i].type === 'ERT' || this.itemList[i].type === 'PRT' || this.itemList[i].type === 'Complete') {
         this.updateFlag = true; 
      }
    }
}