Date Published: January 18, 2011
Publisher: Public Library of Science
Author(s): Matthias Egger, Ben D. Spycher, John Sidle, Ralf Weigel, Elvin H. Geng, Matthew P. Fox, Patrick MacPhail, Gilles van Cutsem, Eugène Messou, Robin Wood, Denis Nash, Margaret Pascoe, Diana Dickinson, Jean-François Etard, James A. McIntyre, Martin W. G. Brinkhof, Gregory P. Bisson
Abstract: Matthias Egger and colleagues present a nomogram and a web-based calculator to correct estimates of program-level mortality for loss to follow-up, for use in antiretroviral treatment programs.
Partial Text: The World Health Organization (WHO) estimates that about 4 million people were receiving antiretroviral therapy (ART) in low- and middle-income countries by the end of 2008, with coverage reaching 42% of the estimated 9.5 million in need of ART . Sub-Saharan Africa represented 70% of the estimated treatment need and 73% of the total number of people receiving treatment in low- and middle-income countries at the end of 2008 .
Regular and complete patient follow-up is essential both for the care of individual patients and the monitoring and evaluation of outcomes of ART programmes. Individual treatment decisions can then be made in the light of clinical and laboratory results and the rate of complications and mortality can be accurately estimated at the programme level. Loss to follow-up is, however, an important problem in ART programmes in resource-limited settings ,,,, and poor ascertainment of deaths in patients lost to follow-up may mean that programme-level mortality, i.e. mortality of all patients starting ART, is underestimated ,. Previous analyses of treatment programmes have generally censored follow-up time at the last visit to the clinic, and patients lost to follow-up therefore contributed follow-up time but no deaths – (here referred to as MU). We developed a simple nomogram that allows programme managers to read off a correction factor for a range of plausible mortality rates among patients lost to follow-up. This factor can then be used to assess to what extent the mortality observed among patients retained in care underestimates mortality at the programme level.