There's plenty of great stuff being published at the moment regarding hamstring injuries, especially by David Opar, Ryan Timmins and The NordBoard crew. Recently, they found that soccer players with shorter bicep femoris fascicle length and lower levels of eccentric hamstring strength had 4 and 4.5x greater risk, respectively, of future hamstring injury. Dr Peter Brukner has also written a paper on the difficulty of treating and managing intra-muscular tendon injuries vs MTJ strains. There is also a really good podcast by the BJSM. All worth a read and a listen.
One of my favourite papers though - relevant for those working at community level - is by Freckleton et al (2013) who found that the single leg hamstring bridge was a good screening tool for future hamstring strains in amateur AFL players. Those that couldn't do >20 reps had a greater chance of injury vs those that could do >25 reps.