We would like to apologise for an error that occurred in the paper by McGarrigle et al (Sex Transm Infect 2002;78:398–405). In table 2, under the heading “Name and custodian” the following affiliations should have appeared. Row one: London School of Hygiene and Tropical Medicine, National Centre for Social Research, and Royal Free & University College Medical School. Row six: City University and Department of Primary Care and Population Sciences and Royal Free Centre for HIV Medicine, Royal Free & University Medical College. Row seven: Study on HIV testing. Royal Free Hampstead NHS Trust Hospital and Department of Primary Care and Population Sciences and Royal Free Centre for HIV Medicine, Royal Free & University College Medical School.