title: Estimating the number of people who inject drugs, female sex workers, and men who have sex with men, Unguja Island, Zanzibar: results and synthesis of multiple methods.
abstract: To determine the number of people who inject drugs (PWID), female sex workers (FSW) and men who have sex with men (MSM) living in Unguja Island, Zanzibar in 2011/2012, we applied several, practical population size estimation methods including literature review, unique object multiplier, recapture from the 2007 survey, wisdom of the crowds and service multiplier. We synthesized findings and presented them to a panel of experts in order to determine plausible estimates for each population. The estimates adopted by a panel of experts as being most plausible were 3,000 for PWID, 3,958 for FSW and 2,157 for MSM. We learned that no one method could be concluded to be the standard for all three populations. The estimates we found, though still not perfect, are useful for the HIV programmes serving these populations.
authors.affiliation: Zanzibar AIDS Control Program, Ministry of Health, P.O. Box 1300, Zanzibar, Tanzania, farhat_jowhar@yahoo.com.
authors.forename: Farhat J
authors.initials: FJ
authors.lastname: Khalid
authors.forename: Fatma M
authors.initials: FM
authors.lastname: Hamad
authors.forename: Asha A
authors.initials: AA
authors.lastname: Othman
authors.forename: Ahmed M
authors.initials: AM
authors.lastname: Khatib
authors.forename: Sophia
authors.initials: S
authors.lastname: Mohamed
authors.forename: Ameir Kh
authors.initials: AKh
authors.lastname: Ali
authors.forename: Mohammed J U
authors.initials: MJ
authors.lastname: Dahoma
mesh_terms: D003625:Data Collection / Q000379:methods*; D055030:Drug Users / Q000706:statistics & numerical data*; D005260:Female; D018451:Homosexuality, Male / Q000706:statistics & numerical data*; D006801:Humans; D008297:Male; D011159:Population Surveillance / Q000379:methods*; D011477:Sex Work / Q000706:statistics & numerical data*; D060386:Sex Workers / Q000706:statistics & numerical data*; D012725:Sexual Behavior / Q000706:statistics & numerical data; D015819:Substance Abuse, Intravenous / Q000453:epidemiology