If you want to check whether certain fields are filled in, you can use the template below. 

In this template, there are 2 fields: 

Replace the labels and variable names in the template with your own. 

'##allowempty##';
var req_labels = ["Gender", "Year of Birth"];
var req_fields = ["{dem_pat_gender}", "{dem_pat_yob}"];
var incomplete = false;
var missingVars = "";
req_fields.forEach(checkCompleteness);
if(incomplete === true){
 "Fields are missing: " + missingVars;
}else{
 "Yes";
}
function checkCompleteness(value, index, array) {
 console.log(value);
 if(value == "'NA'" ){
 incomplete = true;
 missingVars += req_labels[index];
 missingVars += ", ";
 }
}

If not all fields are filled in, the calculation will show "Fields are missing: ", followed by the field labels of the fields that are empty. If all fields are filled in, the calculation will have the value "Yes". You can choose to add a data validation message if the calculation field value is not equal to "Yes".