PT  - JOURNAL ARTICLE
AU  - H Russell Bernard
AU  - Tim Hallett
AU  - Alexandrina Iovita
AU  - Eugene C Johnsen
AU  - Rob Lyerla
AU  - Christopher McCarty
AU  - Mary Mahy
AU  - Matthew J Salganik
AU  - Tetiana Saliuk
AU  - Otilia Scutelniciuc
AU  - Gene A Shelley
AU  - Petchsri Sirinirund
AU  - Sharon Weir
AU  - Donna F Stroup
TI  - Counting hard-to-count populations: the network scale-up method for public health
AID  - 10.1136/sti.2010.044446
DP  - 2010 Dec 01
TA  - Sexually Transmitted Infections
PG  - ii11--ii15
VI  - 86
IP  - Suppl 2
4099  - http://sti.bmj.com/content/86/Suppl_2/ii11.short
4100  - http://sti.bmj.com/content/86/Suppl_2/ii11.full
SO  - Sex Transm Infect2010 Dec 01; 86
AB  - Estimating sizes of hidden or hard-to-reach populations is an important problem in public health. For example, estimates of the sizes of populations at highest risk for HIV and AIDS are needed for designing, evaluating and allocating funding for treatment and prevention programmes. A promising approach to size estimation, relatively new to public health, is the network scale-up method (NSUM), involving two steps: estimating the personal network size of the members of a random sample of a total population and, with this information, estimating the number of members of a hidden subpopulation of the total population. We describe the method, including two approaches to estimating personal network sizes (summation and known population). We discuss the strengths and weaknesses of each approach and provide examples of international applications of the NSUM in public health. We conclude with recommendations for future research and evaluation.