Does the survey suffer from “main street bias”, i.e., the flaw of choosing housholds near main streets that may be particularly likely to have been exposed to violence?
The Lancet article provides the following details of how households were selected in the survey: The third stage [of constructing the sample] consisted of random selection of a main street within the administrative unit from a list of all main streets. A residential street was then randomly selected from a list of residential streets crossing the main street. On the residential street, houses were numbered and a start household was randomly selected. Some commentators have suggested the method of using main streets could have biased the sample. If households near main streets were more likely to be included in the sample, and such households had a higher mortality rate than other households, then the total mortality rate could be biased upward. This possibility was raised by Neil Johnson and Sean Gourley, phycisists at Oxford University and Michael Spagat, an economist at Royal Holloway, University of London. The suggestion was first publicised in an article in Science: “Neil Johnson a
