Which of the following is NOT a characteristic of narrative reviews?

Narrative reviews are primarily characterized by their qualitative synthesis of existing literature rather than a systematic approach to data collection. They typically express an expert's perspective, provide an overview of relevant studies, and are often published in journals as a way to summarize and discuss the state of a specific research area.

The hallmark of narrative reviews is that they do not follow a systematic methodology for gathering and analyzing data, which differentiates them from systematic reviews. Instead, they may draw upon various studies without a structured process, leading to a personal interpretation of the findings. This lack of a systematic collection of data is what makes this characteristic not applicable to narrative reviews.

In contrast, the other characteristics reflect common attributes of narrative reviews: they indeed express the perspectives of experts, offer a broad overview of literature available on a topic, and are frequently published in academic journals to contribute to ongoing conversations in the field.