My right thumb and forearm are 'dominant', so I'm strongly right-handed.
That's only two out of a long list of such tests: I can't remember most of the others. The only one which springs to mind is: hold the fingers of one hand behind your back between thumb and fingers of the other hand ("At Ease" in other words). The hand doing the holding is dominant.
I personally have something called "shared dominance": the side of the brain most correlating to the activity concerned takes charge. Writing and drawing are right-brain, so I do them left handed. Punching and kicking are left-brain, so I do them right handed. But while I write with the left, and draw with the left, I use a mouse with the right (because my brain sees that as a technical activity, and thus left-brain). Except because it's in the right I can't draw very well with it! I eat right-handed, but both thumb and forearm are left. But at ease is right. I have a right dominant eye (which is usually pretty well correlated to handedness) and shoot right handed.
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