Evidently the Jewish council in the Theresienstadt Ghetto operated a (severely underresourced) hospital and issued death certificates. Is there any reason to consider the dates on them reliable, or at least conventional? What about the causes of death? Should we perhaps suppose the information is entirely deceptive, or alternatively relatively sound throughout?
Random example: LÖWYOVÁ ANNA: DEATH CERTIFICATE, GHETTO TEREZÍN, National archives Prague, Židovské matriky, Ohledací listy - ghetto Terezín, Band 16. Terezín Initiative Institute, National Archives, Prague.
I would expect the dates to be rather accurate. Generally, I'd expect causes of death to be covered up by approximation rather than outright lying. Anna Löwyova's certificate does seem suspicious, though. According to the records, she presented with dementia precox and was ruled to have enterocolitis. Enterocolitis is entirely plausible in concentration camps, but it's fair to remain skeptical.
In two documents, both patients presented with "marasmus," which essentially means weakness, an evident result of starvation. One cause of death is listed as "marasmus" while the other seems to have been corrected, from "adynamia" – essentially saying she lacked strength due to a mental condition – to heart failure. http://www2.holocaust.cz/en/document/DOCUMENT.ITI.13246 http://www2.holocaust.cz/en/document/DOCUMENT.ITI.2960
I would certainly read between the lines and to look for patterns, if you were spending more time with these archives. Terezin itself wasn't an extermination camp, though, so I'd try to reconcile lists like these with documents from Sachsenhausen and Auschwitz-Birkenau and see how those deaths were documented.