Async parallel with object only last result - node.js

Question

I'm having an issue with async parallel. This is my current code:
// Tasks object for async
var Tasks = {};
// Go through the items
for(index in items) {
var itemName = items[index];
Tasks[index] = function(callback) {
self._requestItem(currency, appID, itemName, function(err, item) {
if( err) {
callback(err, null);
return;
}
callback(null, { "name": itemName, "data": item });
});
}
}
// Go through tasks, using async parallel
this._async.parallel(Tasks, function(err, results) {
console.log(err, results);
});
Each items entry is unique. But when the parallel finishes it shows every result like the last one. For example if I have 3 items in items then async results outputs 0, 1 the same as 2.
null { '0':
{ name: 'Test 3',
data:
{ success: true,
price: 17.02 } },
'1':
{ name: 'Test 3',
data:
{ success: true,
price: 17.02 } },
'2':
{ name: 'Test 3',
data:
{ success: true,
price: 17.02 } } }
Why does it do this? If I use 2 items in items it again copies the result from 1 to 0.
Adding snippet of _requestItem as requested.
Manager.prototype._requestItem = function(currency, appID, itemName, callback) {
var self = this;
this._request({
uri: this._uri,
baseUrl: this._baseUrl,
json: true
}, function(err, res, body) {
if( ! err && res.statusCode !== 200) {
if(self._errorCodes[res.statusCode] !== undefined) {
callback(self._errorCodes[res.statusCode], null);
} else {
callback('Unsuccessful response (' + res.statusCode + '). Is the API having issues?', null);
}
} else if( ! err && res.statusCode === 200) {
callback(null, body);
} else {
callback(err, null);
}
});
}

Answer 1

No matter what is the content of the body of the _requestItem() function the value of the name attribute on the response array elements shouldn't be the same if the elements of the items array are unique.
The only error i can see is the fact that index is declared as a global variable but this shouldn't be the cause of the problem.
I suggest you to inspect the content of the items variable before the code enters the for loop (to see if it has been corrupted before this point). Debugging is a good idea in this case.
A better implementation would be:
var tasks = items.map(function(itemName){
return function(callback) {
self._requestItem(currency, appID, itemName, function(err, item) {
if( err) {
callback(err, null);
return;
}
callback(null, { "name": itemName, "data": item });
});
}
});
// Go through tasks, using async parallel
this._async.parallel(tasks, function(err, results) {
console.log(err, results);
});