Soo Young Kim
Department of Family Medicine, Kangdong Sacred Heart Hospital, Hallym University College of Medicine, Seoul, Korea

A protocol is defined as “the detailed plan of a study.” Every study should have an explicitly written protocol. According to the Declaration of Helsinki, “Every research study involving human subjects must be registered in a publicly accessible database before recruitment of the first subject.” The International Committee of Medical Journal Editors mandated the registration of all clinical trial protocols. The primary reason for the registration of protocols is to prevent publication bias. Reviewing only published research results leads to an overestimation of the research results causing publication bias where positive results lead to increased submissions, publications, and a rapid turnaround time for publication. Registering all protocols significantly reduces the risk of publication bias.

The second reason why protocols should be registered is to reduce the risk of selective outcome reporting bias, which refers to reporting only positive outcomes from a specific intervention.
Temporarily, protocols were subject to registration alone, and not publication. However, this trend has recently undergone changes. A search for “protocol [ti]” in PubMed (https://pubmed.ncbi. nlm.nih.gov/) shows a sharp increase from 469 results in 2000 to 9,815 in 2021. The purpose of protocol publication may differ slightly from each perspective; researcher, academia, and society as a whole (Table 1).

Table 1. Purpose of protocol publication

Group	Perspective
Individual researcher	1. Protocol publication is favorable for future publication.
	2. Some journals require protocol publication.
	3. Some journals offer automatic registration.
	4. Authors can receive additional credit.
	5. Methods can be improved through initial feedback.
	6. Some journals cover the publication cost.
	7. Some journals discount the publication cost.
Academia	1. Protocol publication provides the institutional review board with data on the current study.
	2. The publication time is reduced.
	3. Methodological errors and similar issues can be detected at an early stage and can be corrected.
Society	1. Research transparency is increased.
	2. Publication bias is prevented.
	3. Selective outcome reporting bias is prevented.
	4. Duplication of research is avoided.

There are several issues related to protocol publication; the first is the emergence of protocol-only journals. Several international journals have launched journals that publish only protocols, as spinoffs. For example, Nature publishes a journal called Nature Protocols and JMIR Research publishes a protocol-only journal called JMIR Research Protocols.

The second issue is to do with whether it will be protocol registration or publication that predominates. Although this is not easy to predict, there is a strong possibility that authors would push for publication, as they receive credits. Furthermore, considering that protocol publication makes it is easy to manage and promote work in the academic world, it might be advantageous as well.

The third issue is related to the possibilities of publishing protocols in domestic journals in various countries.