Ars Technica has a very interesting article on this subject. Here's an excerpt.
Although survivors frequently talk about entry and exit wounds, it’s difficult to figure out in retrospect precisely what path the lightning took, says Mary Ann Cooper, a retired Chicago emergency physician and long-time lightning researcher. The visible evidence of lightning’s wrath is more reflective, Cooper says, of the type of clothing a survivor had on, the coins they were carrying in their pockets and the jewellery they were wearing as the lightning flashed over them.
Lightning is responsible for more than 4,000 deaths worldwide annually—according to those documented in reports from 26 countries. (The true scope of lightning’s casualties in the more impoverished and lightning-prone areas of the world, such as central Africa, is still being calculated.) Cooper is one of a small global cadre of doctors, meteorologists, electrical engineers and others who are driven to better understand how lightning injures people, and ideally how to avoid it in the first place.
Of every ten people hit by lightning, nine will survive to tell the tale. But they could suffer a variety of short- and long-term effects. The list is lengthy and daunting: cardiac arrest, confusion, seizures, dizziness, muscle aches, deafness, headaches, memory deficits, distractibility, personality changes and chronic pain, among others.
Many survivors have a story that they want to share. In postings online and during annual gatherings of Lightning Strike & Electric Shock Survivors International, they swap tales of their brush with nature’s brutal force. The group has convened in the mountains of the south-eastern US every spring since its first meeting was held by 13 survivors in the early 1990s.
There's more at the link, including a number of survivors' stories.
I was surprised to read the details of how lightning passes through - or around - the victim to the ground. I'd presumed it made its way mostly through the body, but apparently that's not the case; a lot of the charge goes around the body, rather than through it (although one survivor had holes burned through the soles of his shoes - shown below - by the discharge as it grounded).
It's a fascinating article . . . and makes me more determined than ever to get out of the way of thunderstorms!