{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,6]],"date-time":"2026-10-06T01:08:41Z","timestamp":1791248921868,"version":"4.1.0"},"reference-count":51,"publisher":"Wiley","issue":"3","license":[{"start":{"date-parts":[[2023,3,15]],"date-time":"2023-03-15T00:00:00Z","timestamp":1678838400000},"content-version":"vor","delay-in-days":14,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["J Int AIDS Soc."],"published-print":{"date-parts":[[2023,3]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:sec><jats:title>Introduction<\/jats:title><jats:p>Singapore lacks robust data on the sizes of the key populations that are most at risk for HIV. Using the network scale\u2010up method for hidden or hard\u2010to\u2010reach populations, we estimate the sizes of five key populations\u2014male clients of female sex workers (MCFSW), men who have sex with men (MSM), female sex workers (FSW), people who inject drugs (PWID) and transgender people\u2014and profile the ages and ethnicities of respondents with the high\u2010risk contacts they report knowing.<\/jats:p><\/jats:sec><jats:sec><jats:title>Methods<\/jats:title><jats:p>We conducted a cross\u2010sectional online survey between March and May 2019 (<jats:italic>n<\/jats:italic> = 2802) using a network scale\u2010up instrument previously developed for Singapore. Participants were recruited using an existing panel and online advertising, and the sample reweighted by age, sex, ethnicity and education attained to represent the general adult population. We built a Bayesian hierarchical model to estimate the sizes of the five key populations for HIV in Singapore.<\/jats:p><\/jats:sec><jats:sec><jats:title>Results<\/jats:title><jats:p>After adjustment, the sizes of the at\u2010risk populations are estimated to be: 76,800 (95% credible interval [CI]: 64,200\u201391,800) MCFSW; 139,000 (95% CI: 120,000\u2013160,000) MSM; 8030 (95% CI: 3980\u201316,200) FSW; 3470 (95% CI: 1540\u20137830) PWID and 18,000 (95% CI: 14,000\u201323,200) transgender people. Generally, men reported knowing more people in all the high\u2010risk groups; older people reported knowing more MCFSW, FSW and transgender people; and younger people reported knowing more MSM. There was a bimodal effect of age on those who reported knowing more PWIDs: people in their 20s and 60s reported more contacts.<\/jats:p><\/jats:sec><jats:sec><jats:title>Conclusions<\/jats:title><jats:p>This study demonstrates that a size estimation study of hidden populations is quickly and efficiently scalable through using online surveys in a socially conservative society, like Singapore, where key populations are stigmatized or criminalized. The approach may be suitable in other countries where stigma is prevalent and where barriers to surveillance and data collection are numerous.<\/jats:p><\/jats:sec>","DOI":"10.1002\/jia2.25973","type":"journal-article","created":{"date-parts":[[2023,3,15]],"date-time":"2023-03-15T12:26:56Z","timestamp":1678883216000},"update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Application of the network scale\u2010up method to estimate the sizes of key populations for HIV in Singapore using online surveys"],"prefix":"10.1002","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4094-4463","authenticated-orcid":false,"given":"Sharon Esi Duoduwa","family":"Quaye","sequence":"first","affiliation":[{"name":"Saw Swee Hock School of Public Health National University of Singapore and National University Health System  Singapore"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuwei","family":"Cheng","sequence":"additional","affiliation":[{"name":"Department of Statistics University of Chicago  Chicago Illinois USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rayner Kay Jin","family":"Tan","sequence":"additional","affiliation":[{"name":"Saw Swee Hock School of Public Health National University of Singapore and National University Health System  Singapore"},{"name":"University of North Carolina Project \u2013 China  Guangzhou China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Joel R.","family":"Koo","sequence":"additional","affiliation":[{"name":"Saw Swee Hock School of Public Health National University of Singapore and National University Health System  Singapore"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kiesha","family":"Prem","sequence":"additional","affiliation":[{"name":"Saw Swee Hock School of Public Health National University of Singapore and National University Health System  Singapore"},{"name":"London School of Hygiene and Tropical Medicine  London UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alvin Kuo Jing","family":"Teo","sequence":"additional","affiliation":[{"name":"Saw Swee Hock School of Public Health National University of Singapore and National University Health System  Singapore"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alex R.","family":"Cook","sequence":"additional","affiliation":[{"name":"Saw Swee Hock School of Public Health National University of Singapore and National University Health System  Singapore"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2023,3,15]]},"reference":[{"key":"e_1_2_11_2_1","doi-asserted-by":"publisher","DOI":"10.1016\/S2055-6640(20)30058-3"},{"key":"e_1_2_11_3_1","unstructured":"The Joint United Nations Programme on HIV\/AIDS (UNAIDS).HIV prevention among key populations. [Cited 2020 Dec 17]. Available from:https:\/\/www.unaids.org\/en\/resources\/presscentre\/featurestories\/2016\/november\/20161121_keypops"},{"key":"e_1_2_11_4_1","first-page":"1","article-title":"HIV\/AIDS in the South\u2010East Asia region: progress and challenges","volume":"2","author":"Pendse R","journal-title":"J Virus Erad"},{"key":"e_1_2_11_5_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.mpmed.2013.05.005"},{"key":"e_1_2_11_6_1","doi-asserted-by":"publisher","DOI":"10.1097\/COH.0000000000000038"},{"issue":"4","key":"e_1_2_11_7_1","first-page":"306","article-title":"The changing epidemiology of HIV in 2013","volume":"8","author":"Beyrer C","year":"2013","journal-title":"Curr Opin HIV AIDS"},{"key":"e_1_2_11_8_1","doi-asserted-by":"publisher","DOI":"10.1002\/jia2.25344"},{"key":"e_1_2_11_9_1","unstructured":"The Joint United Nations Programme on HIV\/AIDS (UNAIDS).UNAIDS warns that HIV\u2010related stigma and discrimination is preventing people from accessing HIV services. [Cited 2021 Mar 2]. Available from:https:\/\/www.unaids.org\/en\/resources\/presscentre\/pressreleaseandstatementarchive\/2017\/october\/20171002_confronting\u2010discrimination"},{"key":"e_1_2_11_10_1","unstructured":"The Joint United Nations Programme on HIV\/AIDS (UNAIDS).Key population groups including gay men and other men who have sex with men sex workers transgender people and people who inject drugs. [Cited 2021 Jan 21]. Available from:https:\/\/www.unaids.org\/en\/topic\/key\u2010populations"},{"key":"e_1_2_11_11_1","unstructured":"MOH.Update on the HIV\/AIDS situation in Singapore 2019. 2020 [cited 2020 Sep 28]. Available from:https:\/\/www.moh.gov.sg\/resources\u2010statistics\/infectious\u2010disease\u2010statistics\/hiv\u2010stats\/update\u2010on\u2010the\u2010hiv\u2010aids\u2010situation\u2010in\u2010singapore\u20102019"},{"key":"e_1_2_11_12_1","unstructured":"Action for AIDS Singapore.Community Blueprint: ending HIV transmission and AIDS in Singapore by 2030. [Cited 2021 Jan 21]. Available from:https:\/\/afa.org.sg\/endingHIV"},{"key":"e_1_2_11_13_1","doi-asserted-by":"publisher","DOI":"10.1186\/s12939-019-1084-1"},{"key":"e_1_2_11_14_1","doi-asserted-by":"publisher","DOI":"10.1007\/s12119-020-09707-7"},{"key":"e_1_2_11_15_1","doi-asserted-by":"publisher","DOI":"10.1177\/1363460718780216"},{"key":"e_1_2_11_16_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.socscimed.2020.112867"},{"key":"e_1_2_11_17_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.socscimed.2015.11.010"},{"key":"e_1_2_11_18_1","doi-asserted-by":"publisher","DOI":"10.1111\/j.1467-9566.2010.01276.x"},{"key":"e_1_2_11_19_1","doi-asserted-by":"publisher","DOI":"10.1017\/asjcl.2015.1"},{"key":"e_1_2_11_20_1","doi-asserted-by":"publisher","DOI":"10.1136\/sextrans-2018-053747"},{"key":"e_1_2_11_21_1","doi-asserted-by":"publisher","DOI":"10.1002\/jia2.25119"},{"key":"e_1_2_11_22_1","doi-asserted-by":"publisher","DOI":"10.7448\/IAS.18.2.19438"},{"key":"e_1_2_11_23_1","doi-asserted-by":"publisher","DOI":"10.1002\/jia2.25125"},{"key":"e_1_2_11_24_1","doi-asserted-by":"publisher","DOI":"10.1002\/jia2.25146"},{"key":"e_1_2_11_25_1","doi-asserted-by":"publisher","DOI":"10.7448\/IAS.16.3.18881"},{"key":"e_1_2_11_26_1","doi-asserted-by":"publisher","DOI":"10.1136\/sti.2010.044446"},{"key":"e_1_2_11_27_1","doi-asserted-by":"publisher","DOI":"10.1097\/01.aids.0000172879.20628.e1"},{"key":"e_1_2_11_28_1","doi-asserted-by":"publisher","DOI":"10.1007\/s10461-014-0943-4"},{"key":"e_1_2_11_29_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.drugpo.2016.01.013"},{"key":"e_1_2_11_30_1","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pone.0147413"},{"key":"e_1_2_11_31_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.ijresmar.2010.08.003"},{"key":"e_1_2_11_32_1","doi-asserted-by":"publisher","DOI":"10.4135\/9781412973380.n6"},{"key":"e_1_2_11_33_1","unstructured":"Singapore Census of Population.Statistical Release 1: Demographic Characteristics Education Language and Religion. Base. 2020 [cited 2022 May 20]. Available from:http:\/\/www.singstat.gov.sg\/publications\/reference\/cop2020\/cop2020\u2010sr1\/census20_stat_release1"},{"key":"e_1_2_11_34_1","doi-asserted-by":"publisher","DOI":"10.1093\/aje\/kwr246"},{"key":"e_1_2_11_35_1","doi-asserted-by":"publisher","DOI":"10.1201\/b16018"},{"key":"e_1_2_11_36_1","unstructured":"PlummerM.JAGS: a program for analysis of Bayesian graphical models using Gibbs sampling. Working Papers.2003."},{"key":"e_1_2_11_37_1","first-page":"169","volume-title":"Bayesian statistics, Vol. 4","author":"Geweke J","year":"1992"},{"key":"e_1_2_11_38_1","doi-asserted-by":"publisher","DOI":"10.1287\/opre.31.6.1109"},{"key":"e_1_2_11_39_1","doi-asserted-by":"publisher","DOI":"10.1002\/9780470316696"},{"issue":"6","key":"e_1_2_11_40_1","first-page":"S17","article-title":"Size estimation of injecting drug users through the network scale\u2010up method in Thailand","volume":"98","author":"Kanato M","year":"2015","journal-title":"J Med Assoc Thai"},{"key":"e_1_2_11_41_1","doi-asserted-by":"publisher","DOI":"10.5365\/wpsar.2014.5.2.008"},{"key":"e_1_2_11_42_1","unstructured":"The Joint United Nations Programme on HIV\/AIDS (UNAIDS).Recommended population size estimates of men who have sex with men on JSTOR. [Cited 2022 May 23]. Available from:https:\/\/www.jstor.org\/stable\/resrep30140?seq=1"},{"key":"e_1_2_11_43_1","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pone.0031184"},{"key":"e_1_2_11_44_1","doi-asserted-by":"publisher","DOI":"10.1186\/s12889-015-2132-4"},{"key":"e_1_2_11_45_1","doi-asserted-by":"publisher","DOI":"10.1136\/sti.2003.008342"},{"issue":"3","key":"e_1_2_11_46_1","first-page":"793","article-title":"Decriminalisation of same\u2010sex relations and social attitudes: an empirical study of Singapore","volume":"47","author":"Chua L","year":"2017","journal-title":"Hong Kong Law J"},{"key":"e_1_2_11_47_1","unstructured":"MathewsM LimL.Religion morality and conservatism in Singapore.Institute of Policy Studies;2019."},{"key":"e_1_2_11_48_1","doi-asserted-by":"publisher","DOI":"10.1136\/sextrans-2018-053866"},{"key":"e_1_2_11_49_1","unstructured":"Statista Research Department.Singapore: total drug abusers by ethnicity 2020. Statista. [Cited 2021 Mar 17]. Available from:https:\/\/www.statista.com\/statistics\/1007694\/total\u2010drug\u2010abusers\u2010by\u2010ethnicity\u2010singapore\/"},{"issue":"2","key":"e_1_2_11_50_1","first-page":"40","article-title":"Exploring constructions of the \u2018drug problem\u2019 in historical and contemporary Singapore","volume":"7","author":"Abdullah N","year":"2005","journal-title":"N Z J Asian Stud"},{"key":"e_1_2_11_51_1","doi-asserted-by":"publisher","DOI":"10.1177\/0081175016665425"},{"key":"e_1_2_11_52_1","unstructured":"Asia Internet Stats by Country and 2022 Population Statistics. [Cited 2022 May 23]. Available from:https:\/\/www.internetworldstats.com\/asia.htm"}],"container-title":["Journal of the International AIDS Society"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/jia2.25973","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/full-xml\/10.1002\/jia2.25973","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/jia2.25973","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2024,8,7]],"date-time":"2024-08-07T05:12:49Z","timestamp":1723007569000},"score":1,"resource":{"primary":{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/10.1002\/jia2.25973"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2023,3]]},"references-count":51,"journal-issue":{"issue":"3","published-print":{"date-parts":[[2023,3]]}},"alternative-id":["10.1002\/jia2.25973"],"URL":"https:\/\/doi.org\/10.1002\/jia2.25973","archive":["Portico"],"relation":{},"ISSN":["1758-2652","1758-2652"],"issn-type":[{"value":"1758-2652","type":"print"},{"value":"1758-2652","type":"electronic"}],"subject":[],"published":{"date-parts":[[2023,3]]},"assertion":[{"value":"2021-10-19","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2022-07-20","order":2,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2023-03-15","order":3,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}],"article-number":"e25973"}}