It's just a matter of getting her to hold still long enough to be able to ruffle her feathers and give her a good checking over. Puncture wounds from claws may be hard to find unless you put her under the magnifying glass so to speak. If you don't find any puncture wounds, consider yourself lucky. I would give her a few days worth of electrolytes/probiotics in her water and keep your birds under cover because Mr or Miss hawk will surely return to the buffet table now that it knows that chicken is being served.
Unfortunately there is no permanent solution to Bird of Prey attacks other than not free ranging your birds and keeping their run covered with netting, tarps or hardware cloth whichever fits your budget.
Free ranging means that you will always be facing the possibility of predator loss so the matter is a personal choice. We have an over abundance of Birds of Prey around our farm. Everything from Bald Eagles to Owls and as a result it is too hazardous to even consider free ranging our flock.
Sounds as though your hen was a very lucky girl to get off with just a few scratches. Keep an eye on them and be ready to put blue kote on it if you notice any pecking going on from your other birds. Don't get it in her eyes. I generally use a q-tip soaked in blue kote when applying it to any areas around their heads.
