IYH Dear Mohammad Muayad Assaf

You were involved in data analysis and figures production, which are significant contributions. With the caveat that this is domain dependent: it could be proper to list you as a co-author (typically a 3rd or 4th author in the middle) and a star next to your name explaining in a footnote "M.M.A worked on data analysis and figures". You see this scheme in many papers. If the main authors are not amenable to that, for sure you should be mentioned in the acknowledgments.

I see your are an M.D. so I looked it up:

ICMJE | Recommendations | Defining the Role of Authors and Contributors

"According to the International Committee of Medical Journal Editors (ICMJE), authorship should be based on four criteria:

Contributors who do not meet all four criteria should be acknowledged but are typically not listed as authors. These contributors may have provided valuable resources and assistance with planning and conducting the research but may not have written or edited the research paper. They are typically listed at the end of the article along with a precise description of each person’s contribution.

Practices can vary between different fields and journals, and not all have adopted this system."

This is a grey area.

Usually, research assistance is named and recognised by the authors, but not mentioned as authors themselves if they did not participate in writing the narrative.

This said, nothing impedes it. In this case, and to be on firm ethical ground, I would recommend mentioning the contribution of each of the different authors in a foot-note, first page or last one.

This is usually what is done for institutional papers, where authors and contributors may not be mentioned at all on the front page, but are listed at the beginning of the report.

My two cents...

Before the 1970s most authors included results as tables and diagrams but without any statistical evidence most such papers got rejected. most of the funding agencies demanded full description of planned data analysis (including most of animal science journals). All this made us the statisticians important as team members of experimental projects and we were given co-authorships. So, it is a matter of educating your research workers about the importance and quality enhance contribution of data analysis.

After reading the comments, I came to realise that the issue is context-dependent.

In laws (and also in economics), it is not usual to mention research assistants as authors on the front page. They may or may not be acknowledged in the paper (usually, not if they are salaried by the firm). In my(old) time, typists were also mentioned, by the way, because the original paper were (badly) manuscript. Authors are usually listed by alphabetic order.

In hard sciences, it goes the opposite: papers have a long list of authors, the order in the list supposingly providing an idea of the substantive contribution in writing the paper or conducting the research. It is customary in this case to add everyone, from the Lab's director down to the guy managing the coffee machine.

In the end, the answer is "it depends".

I am grateful for all your responses

Thank you all