The phrase "as frequently demonstrated" is correct and usable in written English.
It can be used to refer to something that has been shown or proven multiple times in various contexts.
Example: "The effectiveness of this method, as frequently demonstrated in previous studies, cannot be overlooked."
Alternatives: "as often shown" or "as commonly illustrated".
That North Korea has sought to acquire H-bomb technology is beyond doubt, as is its frequently demonstrated ability to exert a form of international blackmail.
But as Davis frequently demonstrated, you can tell only half the story without a healthy dose of darkness.
Keratin 19, an intermediate filament protein responsible for the structural integrity of epithelial cells as a gene, frequently demonstrated promoter methylation in sporadic RCC but not in normal kidney tissue from RCC patients and non-cancer patients.
The importance of depressive symptomatology in type 1 diabetes is expected, as it has been frequently demonstrated that those with high depressive symptomatology are at an increased mortality (12) and morbidity risk (including diabetes complications) (13).
As early as 1991, we reported that KRAS mutations in cancer cell lines frequently demonstrated complete or relative MASI [3] (Fig. 1b).
As evident from this study, serotype O139 is still the most frequently demonstrated oedema disease inducing serotype also in Sweden.
This has been frequently demonstrated where there is suspicion of pulmonary infection, as many noninfectious processes present with lung infiltrates and fever, falsely attributed to pneumonia [ 30, 31].
There are many Americans who are, frankly, unnerved by his frequently demonstrated contempt for due process.
Associated paralabral cysts are frequently demonstrated on MRI [45].
1 In particular, postmenarchal and premenopausal women may develop oestrogen-dependent diseases such as endometriosis and uterine myoma. 2 While some diseases decline in frequency after menopause, others, such as hyperlipidaemia, occur more frequently, demonstrating that menopause represents a major transition event in a woman's life course.
