Read the Wikipedia entry. Read the portion about the original study that coined the term ROGD. It's a laughable 'study'. There are any number of 'studies' at any point of time without any actual rigor.
"ROGD (Rapid Onset Gender Dysphoria) has never been recognized by any major professional association as a valid mental health diagnosis, and its use has been discouraged by the American Psychological Association, the American Psychiatric Association, the World Professional Association for Transgender Health, and other medical organizations due to a lack of reputable scientific evidence for the concept."
"In 2021, the American Psychological Association and the American Psychiatric Association cosigned a statement with 120 other medical organizations calling for ROGD not to be used in diagnostic or clinical settings due to a lack of reputable scientific evidence for the concept. The statement also criticized the proliferation of misinformation supporting the concept of ROGD targeted at parents and clinicians and the concept's use to justify laws targeting the rights of transgender youth in the United States."