Hopkins's pamphlet is a primary source and it is also an interested one, so historians read it beside the surviving assize and gaol records rather than instead of them. Malcolm Gaskill's reconstruction of the East Anglian campaign works that way, and the two accounts do not match. The pamphlet presents an orderly investigator answering reasonable questions; the records show a sequence of local panics, chains of accusation running from one confession to the next, and defendants held in conditions that killed some of them before trial.
The number of people who died in the campaign is disputed and no responsible figure should be quoted as settled. Estimates in the scholarly literature run from around a hundred upward, and higher numbers circulate in popular accounts on weaker foundations; the surviving records are incomplete, some assize files are lost, and deaths in gaol are recorded unevenly. What is not disputed is that this was the deadliest concentration of witch prosecution in English history and that it happened in about three years.
Hopkins himself died in 1647, most likely of consumption, and was buried at Mistley. The story that he was himself put to the swimming test and hanged as a witch is a later legend with no contemporary support. Stearne published a longer defence of their work in 1648. Both men died in their beds, which is more than can be said for the people they accused.