Sadly this is not just a problem in Iran, it ia problem in all published research. One of the authorities on RCT’s has said only 30% of the research published is valid. When I look at studies , no matter where they come from, it is important to look at the journal, the researchers, the study design, whether the abstract says what the study says, the financial backers, and yes, Iran, India, China and the US have issues with fraudulent research.
Here is one source from The Townsend Newsletter citing concerning research practices from Iran:
https://www.townsendletter.com/article/441-apparent-fraudu