Scope issues with javascript (node.js + mongo.db)

I am encountering some problems with my convertKey function, and I suspect it is due to scope issues. Basically, I try to retrieve a record from my mongo database and store it in a count variable, but when I try to return it, I get "undefined". Surprisingly, console.log(nameSearch + count) works, while return nameSearch + count doesn't. Would really appreciate it if someone could help me on this!

var dbUrl = "kidstartnow",
  collections = ["students", "studentsList"];
var db = require("mongojs").connect(dbUrl, collections);

function Student(name, src) {
  this.name = name.toLowerCase();

  //this function does not work
  this.key = convertKey(this.name);

  this.src = src;
  this.pointsTotal = 0;

  //inserts student into database
  var student = {name: this.name, key: this.key, pointsTotal: this.pointsTotal,
    src: this.src
  };
  db.students.insert(student);

  //converts name to a key by stripping white space and adding a number behind and ensures keys are unique
  //concatenates names together to form namesearch, and checks if entry exists in studentsList
  function convertKey(name) {

    var nameSearch = name.replace(/\s/g, ''),
      count = 1;



    db.studentsList.find({name: nameSearch}, function(err, student) {      
      //if nameSearch does not exist in studentsList, create entry and sets count to 1
      if(err || !student.length) {
        db.studentsList.insert({name: nameSearch, count: 1});
        count = 1;
        return nameSearch + count;
      }

      //if entry does exist, increments count by 1
      else {
        db.studentsList.update({name: nameSearch}, {$inc: {count: 1}}, function(err) {
          if(err) {
            console.log("Error incrementing records");
          }

          db.studentsList.find({name: nameSearch}, function(err, student) {
            count = student[0].count;
            //this works
            console.log(nameSearch + count)
            //but this doesn't
            return nameSearch + count;
          });
        });
      }
    });
  };
}