Negative relationship between unsatisfactory reading levels and endorsed librarian staffing
There is a negative and statistically significant relationship between unsatisfactory reading levels and endorsed librarian staffing trends.
Schools that either maintained or gained an endorsed librarian between 2005 and 2011 tended to have fewer students scoring unsatisfactory in reading in 2011 (i.e., lower scores) (28% and 26%, respectively) and to have reduced that problem more since 2005 (i.e., lower increase) than schools that either lost their librarians or never had one (both at 34%). Conversely, schools that either lost a librarian during this period or never had one (32% and 34%) tended to have more students scoring unsatisfactory in 2011 and to have seen that problem increase more since 2005 than schools that maintained or gained a librarian (21% and 30%).
Notably, schools with the largest percentage of lower unsatisfactory reading scores in 2011 and lower increases in that figure between 2005 and 2011 (34%) were those that gained an endorsed librarian during the interval. As with advanced reading scores, if an endorsed librarian is doing her or his job well, this is what one would expect.