Thanks!
I'm not sure what criteria they use for reporting a negative item other than payment history. When I personally tried to get the CRA to change anything, it never happened. I finally had to write to the creditor, explaining why I thought the information was wrong and requesting that they contact the CRA and have it fixed.
Example: my children were authorized users on my accounts. But my delinquent history showed up on their reports. I notified CRA and they did absolutely nothing. I wrote to the creditors, telling them that my children were only authorized users and under the law were not responsible for my debt. My creditors contacted CRA and had it removed.
Example: my daughter had a credit card account that she didn't remember opening. It so happened that her husband at the time (now ex) opened a credit card in her name (his credit was lousy). We disputed it with CRA and it came back as valid. We wrote to creditor and explained the situation; asked them to provide a copy of the application showing she applied, and if they could not to remove it. The creditor removed it.
So in my opinion it's best to deal with the creditor. I hope this helps.