Sentence examples for been difficult to document from inspiring English sources
The civilian toll had been difficult to document and until then, impossible to film, let alone broadcast.
And the school improvements, while frequently confirmed anecdotally and through individual school test scores, have been difficult to document in ways that satisfy rigorous educational research standards.
An agroecology similar to that proposed for the Archaic Southwest probably existed among the Eastern Archaic peoples, but it has been difficult to document.
A variety of safety initiatives have been shown to improve patient outcomes in several centers in the United States, but it has been difficult to document the expected association between those results and reduced liability premiums.
Mr. Kerik said yesterday that he views the strength of his program as its ability to use tools, such as public opinion surveys and written reports, to accurately measure improvement in an area where progress has long been difficult to document.
The commissioner explained that he hoped to use the precinct commanders' meeting reports and the survey to measure how well the police respond to neighborhood issues, and thus hold commanders responsible for improving community relations, an area where progress has long been difficult to document.
But they are difficult to document.
Similarly the beneficial distributional effects are difficult to document.
"For football and baseball players, explosive muscle mass might relate to more power, but it is difficult to document that it leads to better performance".
