They increased Scratch zombification chance, tested and proven.

[trunks_budo]

In my past four worlds.

First world - scratched once, zombified after one day.
Second world - scratched once, clear. Scratched a second time, zombified. 
Third world - Scratched once, zombified after one day.
Fourth world - Scratched once, zombified after one day. 

Numbers don't lie. I really wish Indie Stone didn't commit to under-the-hood updates without telling anybody, it's low, and pathetic. We ALL operate with the understanding that scratches are a 7% chance, but guess what? That is no longer the case, as proven by me. 

[Toshis]

Dunno, my character got scratched few times and didnt zombify. Maybe you've got streak of bad luck?

 

edit:

 

5 times isnt large enough sample. Test it for 100 times.

[Toshis]

Lets say there is 7% chance to get zombified from scratch (approximately 1 in 14 chance).  I've generated a sample of 1000 random numbers between 1 and 14 and exported it into word document. Lets say 14th number is unwanted, so i've highlighted it in green. Then i highlighter larger streak of "bad luck" in red square. Its rare, but it is possible:

 

 

Another example:

 

 

Not saying that you're right or wrong, just that it is possible. You have to test it many, many times to get more accurate answer or dig into the game code.

[aamigogorina]

you'll need a considerably larger sample space to make those kinds of conclusions. what toshis explained basically, though in his example experiment you'd be able to calculate the rough probability of getting infected because of the larger sample size(if the results were actually picked from testing).

 

EDIT: damn i didnt read toshis first post, he basically explained the same thing haha sorry

[DXPOHIHIHI]

You didn't really prove it, you just gave the idea but you didn't validate it properly, when we are talking about chances you cant just verify something changed by just a few runs.

[Jamal Money]

Anecdotes should always be viewed with skepticism.  My current, and favorite run ever, has seen 3 scratches so far with none turning me, and I have the trait that makes you more likely to turn.

[Insidiousness]

This kinda reminds me of the lady that was supposed to open a jar that that had different colored marbles in it, and was supposed to guess which color was in majority. She picked up one red marble and just said "they're all mostly red.", from a sample of one.

Genius!