You can't do this validation in the `_.map` as this function will get called for each value in `journalsData`.

Something like this might work:

```javascript
// Concatenate the print- and electronic ISSN's for each journal
var journalsCollection = _.map(journalsData, function(journal) {
    var journalId = _concatJournalIds(journal[1], journal[2]);
    return new Journal(journalId, journal[0]);
});

// Validate each journal
_.each(journalsCollection, function(journal) {
    validator.check(journal.id, {'code': 400, 'msg': 'An invalid ID was passed in for journal: ' + journal.displayName}).notEmpty();
    validator.check(journal.displayName, {'code': 400, 'msg': 'An invalid displayName was passed in for journal: ' + journal.id}).notEmpty()
});
if (validator.hasErrors()) {
    log().error(validator.getFirstError(), 'Error while importing journals from .CSV file');
    return _cleanUpCSVFile(journalsCSV, function() {
        callback(validator.getFirstError());
     });
}

// Ingest the journals
```