This question comes up frequently with Gadolinium Deposition Disease sufferers and the reading of the literature on gadolinium. Understanding the literature is extremely difficult as well, even for experts in Radiology research and publication such as myself, as this work is very specific to certain areas of science - which are not my areas.
The only studies that directly are relevant to GDD sufferers are studies actually performed on GDD sufferers. They would also need to match the clinical scenario. The number of studies to be truly meaningful should be atleast 100 patients, and to see if treatment or no treatment is better management, is to have matched sufferers: age, gender, underlying conditions, duration of disease, prior treatments, and type of GBCA. This should also be done as blinded randomized studies. Currently these studies do not exist, so the best estimates must be made of existing data. It should be emphasized that anecdotal reports are generally worthless. As an example I have heard of anecdotal reports where a man with low-grade prostate cancer undergo total prostatectomy, and swear by the appropriateness of this surgery because they are still alive. The huge fallacy of this assumption is you don't know how this would compare to what would have happened if you had no treatment or radiation therapy, as there are no alternate universes that you live in simultaneously, to compare exactly with each other. Studies need to be large in number and with matched controls to be meaningful. It is important to realize that GDD patients are doing something different with GBCAs than 'normal' individuals, 'normal' animals, and test tube data. Hence it is critical to look at data on patients with GDD. If the patients studied, do not have GDD, they only party reflect the situation of patients with GDD. There is a huge missing difference: patients with GDD are very sick following gadolinium, and all the other above mentioned scenarios, the test-tubes, animals, humans are not. GDD patients are doing something different with GBCAs.
Also when looking at animal studies, human physiologic conditions have to be matched. So regarding the use of ligands, physiologic human equivalent doses of the exact ligand with the exact pacing of chelations is necessary (human-equivalent),for the exact indication, including exact GBCA. The animals also have to have GDD -equivalent disease to be accurately matched. So we recommend chelations no sooner than 1 week apart and quite often at 1 month intervals appears appropriate. This delay allows time for metabolites to re-equilibrate.
Why not perform the studies that need to be done. Two main reasons: time and money. Studies require a lot of time to go through approval phase, to be performed, to be written up and to be published. Usually at least 3 years for all these steps. Money: studies take atleast 1 million dollars of this type. It is very competitive and very difficult to obtain grant money of this amount, and if grant proposals are submitted to organizations like the NIH, this may take at least 3 submissions to obtain a numerical score that would recommend support (a 3 year process)- and this is if it is fortunate enough to get funding. Also it takes enormous energy and focus on the part of the experimenters, especially the principle investigators (PIs). This enthusiasm and energy of PIs often diminishes with age.
In summary: If you have GDD, the only studies that directly pertain to you are matched studies on GDD patients (or GDD animals). All other studies are surrogates of varying and often considerable weakness. Anecdotes are meaningless. If treatment or no treatment is the preferred strategy this can only be determined by relatively large number matched blinded studies. These do not exist. Hence, the best we can do right now is rely on experts who understand what is available to know about GDD; while plan to execute, and wait for others to perform, studies that actually pertain to GDD patients. There is presently no magic bullets. If you think that you are doing worse with chelation, you may actually be doing much worse without chelation. We just don't know, but individual unmatched anecdotes of many patients who have not been treated suggest this is the case. But read my blog on Treatment vs No Treatment as each decision is individual, and only you can make it.