This is a rare, specifically non-fiction post. Except it isn't really, as the boundary between fiction and non-fiction is very - shall we say - blurred; imprecise.
Much children's non-fiction includes examples of things that have happened to real people - case studies, in grown-up speak. Now, if I were writing an academic text, a case study would be well-documented, would use verbatim quotes from someone who had agreed to be interviewed and whom I had met or at least emailed. That sounds like a real case study, doesn't it? Is that what you get in a children's book?
In the good old days of longer lead times and higher fees, I would try to apply this method to case studies in children's non-fiction. But it's not always viable. If I need the story of a child in Eritrea, how am going to find it? Not by going to Eritrea, I can tell you. For the last few years, most case studies have come from the web - of course. Short bits, I'd quote directly and credit with the original name. If I took a lot, and didn't have permission to use the case study, I'd change the names and vary the wording to avoid any permissions disputes. Do you think that's dishonest? How much time do you think someone can allocate to chasing permissions from websites that don't reply when writing a book for £1500 in four weeks? Publishers get what they pay for - actually, they get a lot more than they pay for - and there are corners that have to be cut.
Sometimes, I really did take my case studies from life, often from friends of my daughters. They kindly agreed to talk to me honestly about things such as their substance abuse or criminal activities. They wouldn't thank me for using their real names. Of course, books and their case studies vary. In a recent book about careers in vulcanology, I found lots of real vulcanologists and either emailed them or, if they proved elusive, took the information I needed from their professional websites. In a book about drug abuse, I took stories from real friends, but also testimonies from the web, particularly support groups and fora for drug abusers, and changed the wording and the names. Real stories, but with the details changed.
I haven't done a book based on case studies for a while, and things have changed in the three or four years since the last one. This time I have a totally new approach. There are still people I know who will give me some case studies. (This time it's on charity work in disaster zones and emergencies - please say in the comments if you work in this and I can talk to you! See what I did there? Used my blog as a source of case studies...) Many more are, again, coming from the web. But no longer just from the charity websites I might have used three years ago. This time round, I'm taking them from blogs, from YouTube - there is footage of rescue workers digging people from earthquake rubble, for instance - and from twitter. A quick request on twitter for people to talk to about charity work in emergencies brought in a few offers of stories. There are new ways for voices to be heard and so tracked down, and new ways of asking for help. Twitter means I can ask the whole world, and case studies can come to me - before I had to look for organisations or people to approach.
But remember that when you see in a book 'Sadia of Karachi said...' it probably means 'here are the rewritten words of Ahmed from Islamabad that I found on the Guardian website'. Privacy and copyright concerns, coupled with the tiny amounts of time and money allowed, mean that case studies - while not fictional - are certainly fictionalised. Publishers know this - of course they do; they're not prepared to pay the BBC to quote chunks from their website. (The BBC's proprietorial attitude to comments given them for free on pages financed by our licence fees is scandalous.) Publishers don't admit this goes on - they don't say 'go out and make up some case studies' - but if you sent in your book with a list of people they had to get permission from or pay, they would rapidly tell you where to go. I have, sometimes, been asked to give the contact details of my case studies and have refused. A teenager tells me he uses ketamine and I give his details to a publisher?! NO.
Oh, and look at the contract. You probably have to pay permissions yourself and are responsible for any breach of copyright or privacy cases. So a bit of fictionalising really is the only way if you want to make any money from the contract and keep your house.