The phrase 'repeatedly documented' is grammatically correct and usable in written English.
You can use it to describe situations where something is noted down multiple times. For example, "The patient's symptoms were repeatedly documented in her medical records."
As a senior researcher for Memorial in Chechnya, she had repeatedly documented atrocities committed by the security forces.
There is very little science to explain why, but Dr. Raglin and others have repeatedly documented the effect.
I repeatedly documented the military's many abuses in reports to the U.N. General Assembly and the U.N. Commission on Human Rights.
Here was a scientist who had repeatedly documented the decline of his data; he seemed to have a talent for finding results that fell apart.
And there are times when government spending can provide macroeconomic stimulus, which the C.B.O. has repeatedly documented, to the consternation of Republicans.
Behavioral economics, a new area of research combining economics and psychology, has repeatedly documented how our apparently free choices are affected by the way options are presented to us.
Disparities in health and medical conditions among ethnic and racial groups have been repeatedly documented.
Variability in classifying and selecting levels of fusion in adolescent idiopathic scoliosis (AIS) has been repeatedly documented.
Prior research has repeatedly documented higher placement stability for children who enter kinship care rather than non-relative foster care.
Here, sexual violence is repeatedly documented to the extent of producing a 'pornography of violence', where media and researchers alike are 'trying to outdo each other with the most barbaric gang-rape scenario' (Stearns 2009, para 4).
The contrasting perceptions have been repeatedly documented.
