Fig. 1From: Converting from face-to-face to postal follow-up and its effects on participant retention, response rates and errors: lessons from the EQUAL study in the UKExamples of errors counted in the Dialysis Symptom Index. In the first three questions duplications are shown, with (1) answering both “no” and “yes” simultaneously, (2) answering “no” along with a quantifier for how much the symptom bothers them, and (3) answering two quantifiers together, respectively. The latter two questions show errors related to crossing answers out, with the first example showing a corrected error, and the last example showing an error crossed out but no correctionBack to article page