Absolutely. I researched this extensively because I was confused. I came to find out I was overeating every piece of meat because I was measuring them cooked.
Weigh raw, cook then eat. It's difficult sometimes to take a 12oz steak and try to 'eyeball' a portion to make it 4oz (for example) - do your best, or find a perfect 4oz portion, cook then weigh it - whatever the number, you'll know from then on that you can cook and cut a portion of that weight (it'll be close, but not perfect every time).
I've found personally that a very rough estimate is 4oz of raw meat will yield about 3oz cooked. This will definitely vary from meat to meat, but it's a loose guideline.