Challenges to re‐enrolling perinatally HIV‐infected and HIV‐exposed but uninfected children into a prospective cohort study: strategies for locating and recruiting hard‐to‐reach families

Abstract

Children infected with the human immunodeficiency virus (HIV) are living longer. Studies aimed at understanding the health and well-being of these children as they age into adolescence are enhanced by research designs that include appropriate comparison groups. HIV-exposed but uninfected children are one such comparison group; however, recruitment of this comparison group is challenging because uninfected children may no longer be followed at tertiary care centres, and some may be in foster care or no longer living with their biological parents. This paper describes the recruitment methods, sampling plan, and factors associated with enrolling perinatally HIV-infected children and a comparison group of HIV-exposed but uninfected children into the HIV Follow-up Of Perinatally Exposed Children (PACTS-HOPE) prospective cohort study. The source population consists of HIV-infected and uninfected children originally enrolled in the Perinatal AIDS Collaborative Transmission Study (PACTS). Recruitment took place at paediatric HIV clinics in four US locations between March 2001 and March 2003. A total of 182 HIV-infected and 180 uninfected children were enrolled. Enrolment of uninfected children was much harder than that of infected children because the former often could not be located. After adjusting for site and birth-year category, uninfected children born to white mothers were significantly less likely to be enrolled (P < 0.01). There was a trend for infected and uninfected children of mothers with a history of injection drug use to enrol at lower rates. Although recruitment of the uninfected comparison group was challenging, it was nevertheless facilitated by hierarchical recruitment techniques, involvement of family networks, and continuity of study staff. The PACTS-HOPE cohort will provide opportunities for future research aimed at understanding the unique effects of HIV on the well-being of HIV-infected children.