Disclosing Disability During an Interview?

I had an interview for a great job opportunity today. Before I walked into the agency, I thought about whether I should try mentioning my disability. It’s fairly obvious when talking with me in person. However I did some research on disclosure and found that most people get jobs when they decline to speak about their disabilities during the interview.
I waited for the end of my interview and as part of my final message, I disclosed that my nasal voice and speech stem from birth defects as a physical disability. I did however try to explain that my speech is like an accent; I find that coworkers understand me better as time goes on.
I disclosed in response to someone suggesting that I be upfront and not let people make assumptions. One of my goals this year is to stop making assumptions and asking for further clarification.
Would you or have you disclosed a specific disability during a job interview? Do you think it hurts people’s chances to disclose to possible employers? I would love to know your opinions.