There are several kinds of writing that fall under the umbrella of scientific writing:
Regardless of the kind, all scientific writing aims at presenting data and/or ideas with precision, clarity, and objectivity that allow a reader to evaluate the validity of the results and conclusions based only on the facts presented.
"If the reader is to grasp what the writer means, the writer must understand what the reader needs". Good advice by George D. Gopen and Judith A. Swan (1990).
Both peer-reviewed and refereed journals ARE scholarly journals. The difference lies mainly in the way article review is conducted and the intended audience of a journal.
Most scientific research is initially published in scholarly periodicals. What does ‘scholarly’ mean? Webster's Dictionary defines "scholarly" as
What is a scholarly periodical?
A scholarly periodical is a journal, the main purpose of which is to report on original research or experimentation to make it available to academic audience. The titles of the scholarly journals sometimes contain the words: Journal of..., Quarterly, Review, Research. In citations, the titles are usually abbreviated. Examples of scholarly journals: Brain Research, Cell, JAMA: The Journal of the American Medical Association, Journal of Virology, Science, Nature, New England Journal of Medicine. Some scholarly journals are published by scientific associations, for example, American Geophysical Union or American Society for Microbiology; others are published by scientific publishers such as Elsevier or Marcel Dekker.
Characteristics of a scholarly periodical