Table 1.

Characteristics of studies examining the effectiveness of partner services for HIV and sexually transmitted infections

Study	Intervention and infection	Study design and comparison group	Data sources and time period	Study setting and population
Billock et al., 202149	Intervention: DIS contact tracing services Infections: HIV, syphilis	Design: External control group Comparator: Previously diagnosed PWH who were not reached by DIS	Data: North Carolina Electronic Disease Surveillance system Time period: 01/2013–06/2017	Setting: North Carolina Population: MSM who were diagnosed with HIV or early syphilis Sample: n=2,350 (reached by DIS: n=1,397; not reached by DIS: n=953)
Bocour et al., 201323	Intervention: Field Service Unit (FSU) HIV partner services Infection: HIV	Design: External control group Comparator: Non-FSU participating facilities	Data: NYC HIV Surveillance Registry and FSU database Time period: 2007–2011 (assumed; time period not clearly stated)	Setting: NYC (multiple facilities; details not specified) Population: Residents ≥13 years old newly diagnosed with HIV and reported to the NYC health department Sample: n=10,095 (FSU patients: n=4,108; non-FSU patients: n=5,987)
Brewer et al., 200534	Intervention: Supplementing partner notification contact interviews with interviewing techniques that add recall cues: 1) cues with locations where people meet partners, role relationships, network ties, and first letters of names (“combined location/role/letter/network cue set”); and 2) cues including common first names (“first name cue set”) Infections: Chlamydia, gonorrhea, syphilis	Design: Randomized controlled trial Comparator: Standard cues referring to individual characteristics	Data: El Paso County health department STI program database Time period: 08/2000–06/2001	Setting: Colorado Springs, Colorado Population: Individuals diagnosed with bacterial STIs and who reported multiple sex partners in the past 90 days in interviews with county disease control staff Sample: n=123 (combined cues: n=35, first name cue set: n=41, individual characteristics cues [control]: n=47)
CDC, 199235	Intervention: An intervention campaign by the state health department and CDC to reduce the incidence of early syphilis through increased partner notification and cluster investigation Infection: Syphilis	Design: Pre-post design with no external control group Comparator: 6 weeks before the campaign vs. the first 6 weeks of the campaign	Data: Alabama health department STI databases Time period: 6/17/1991–11/07/1991	Setting: Montgomery County, Alabama Population: Syphilis patients, their sex partners, and their associates at high risk Sample: n=373 patients, 984 sex partners, and 1,446 associates at high risk (sample sizes for the pre- versus post-period were not provided)
Du et al., 200736	Intervention: Partner notification Infection: Gonorrhea	Design: External control group Comparator: Comparison of counties (which we classify in this review as “external control group”) with different levels of partner notification effectiveness (percent of patients interviewed, contact index, partner test positivity, percent of infected partners provided curative treatment, percent of partners unable to be located)	Data: Partner services and surveillance data Time period: 1992–2002	Setting: 15 urban counties in New York, excluding NYC Population: Diagnosed gonorrhea patients Sample: n=100,756 diagnosed index patients, n=37,393 interviewed patients, n=34,807 named sex partners; the sample size for each analysis differed depending on the exposure measure used
Engelgau et al., 199537	Intervention: Intensified partner notification and cluster investigation campaign that increased the number of public health workers assigned to syphilis control activities and hours of STI clinical services; public health workers also received supplemental training and intense supervision on intensified partner notification and cluster investigation techniques Infection: Syphilis	Design: Pre-post design with no external control group Comparator: 6 weeks before the campaign versus the first 6 weeks of the campaign	Data: Montgomery County STI program records Time period: Campaign was implemented 06/17/1991–11/7/1991; study period was 6 weeks before the campaign versus the first 6 weeks of the campaign	Setting: Montgomery County, Alabama Population: Syphilis patients, their sex partners, and their associates in the social network at high risk Sample: Early intervention period (first 6 weeks), n=151 patients, 390 partners, 636 associates at high-risk; control period (6 wk pre-campaign period), n=78 patients, 178 partners, 183 associates at high risk
Golden et al., 200924	Intervention: Partner notification services delivered by public health staff Infection: HIV	Design: External control group Comparator: No partner services	Data: Patient surveys from behavioral surveillance program Time period: 2006–2007	Setting: 1 HIV clinic in Seattle, Washington Population: Random sample of English-speaking HIV patients Sample: n=370 (among eligible participants who attended their clinic appointment, 85% consented to study participation)
Golden et al., 201538	Intervention: Public health expedited partner therapy, comprising local health jurisdictions’ promotion of patient-delivered partner therapy (PDPT) use and prioritized provision of public health partner services Infections: Chlamydia, gonorrhea	Design: Stepped-wedge, community-level randomized design Comparator: Comparison of outcomes between communities that had received the intervention versus those that had not yet received it and within communities (before and after the intervention)	Data: Laboratory data from Infertility Prevention Project and Planned Parenthood of Western Washington clinics; case report forms from medical providers and laboratories; partner services data; and interviews with randomly selected patients Time period: 10/2007–08/2009	Setting: 23 local health jurisdictions in Washington State Population: Heterosexual patients diagnosed with gonorrhea or chlamydia Sample: No sample size reported for the overall study or by treatment group because the study was a community-level randomized trial
Halkitis et al., 201125	Intervention: Partner services Infection: HIV	Design: External control group Comparator: Alternative venue testing via mobile van and social network strategy through inter-agency referrals by 1 community-based organization (note: for our review, we considered these as comparators because they were delivered by investigators rather than DIS or other public health staff)	Data: NYC health department monthly reports of HIV testing data for African American MSM (partner services strategy); cross-sectional surveys and rapid HIV antibody tests administered by investigators (alternative venue testing and social network strategies) Time period: 04/2008–08/2009	Setting: NYC Population: African American MSM aged 18–64 y with previously undiagnosed HIV infection Sample: Partner services, n=49; alternative venue testing, n=400; social networks strategy, n=109
Han et al., 199939	Intervention: Reprioritizing to focus on interviewing patients within high-morbidity geographical areas (“core-targeting interventions”) Note: During a syphilis epidemic, field staff were diverted from gonorrhea to syphilis control activities, described as “reduced-core.” Infection: Gonorrhea	Design: Pre-post design with external control group Comparator: Syracuse, New York (traditional field services)	Data: STI surveillance data and aggregated partner services interview data Time period: 1975–1997 (pre-intervention: 1975–1983, initial full-core: 1984–1988, reduced-core during the syphilis initiative: 1989–1991, full-core: 1992–1997)	Setting: Buffalo/Erie County, New York (intervention) and Syracuse/Onondaga County, New York (control) Population: Residents with reported gonorrhea Sample size not specified; this was a population-based study
Heumann et al., 201750	Intervention: In-person partner services interviews Infections: HIV, syphilis	Design: External control group Comparator: Telephone partner services interviews	Data: Partner services records and the enhanced HIV/AIDS Reporting System (eHARS) Time period: 2010–2014	Setting: King County, Washington Population: All residents with early syphilis or newly diagnosed HIV infection who were interviewed by DIS for partner services Sample: early syphilis, n=1,328 (in-person interviews [treatment]: n=682; telephone interviews [control]: n=646); HIV, n=847 (in-person interviews [treatment]: n=358; phone interviews [control]: n=489)
Hood et al., 201726	Intervention: Partner services, following the integration of HIV surveillance and field services Infection: HIV	Design: External control group Comparator: Newly diagnosed PWH who did not receive partner services	Data: HIV surveillance and field services data Time period: 2010–2015	Setting: King County, Washington Population: All PWH who entered the King County HIVsurveillance system from 2010–2015 Sample: n=1,474 (treatment: n=1,187; control: n=287)
Hoxworth et al., 200327	Intervention: Partner notification Infection: HIV	Design: Pre-post design with external control group (although this is a pre-post design, the extracted results comprise “post” comparisons between groups) Comparator: Patients at 1 Denver HIV counseling and testing site who received a negative HIV test but were at high risk for HIV infection; they did not receive partner notification	Data: Study interviews at baseline, 3 months, and 6 months Time period: 09/1998–04/2000 for recruitment; full study period not clearly specified	Setting: Denver, Colorado Population: Index patients with HIV who were previously interviewed to identify partners, partners who the health department notified regarding HIV exposure, and patients at 1 Denver HIV counseling and testing site who received a negative HIV test but were at high risk for HIV infection (controls) Sample: n=202 (70 index patients, 33 notified partners, and 99 controls)
Katz et al., 201651	Intervention: Revising health departments’ STI partner services programs to provide services to all MSM with early syphilis, gonorrhea, or chlamydia and test all MSM and their sex partners for HIV prior to index patient case closure Infections: HIV, syphilis, gonorrhea, chlamydia	Design: Pre-post design with no external control group Comparator: Pre-intervention period	Data: Matched HIV and STI surveillance and partner services data Time period: 01/2010–10/2014	Setting: Washington State Population: MSM with early syphilis, gonorrhea, or chlamydia without a prior HIV diagnosis Sample: n=8,133 (pre-intervention: n=3,253; intervention period: n=4,880)
Katz et al., 198840	Intervention: Study 1: Field follow-up for patients with chlamydial infection; Study 2: (a) DIS interviews with index patients to elicit partners and encourage patients to refer partners to the clinic and (b) DIS interviews with index patients and field follow-up to named partners Infection: Chlamydia	Design: External control group; although the external groups differed for the 2 studies, the same design was used Comparator: Study 1: Reminder system to come to clinic for chlamydia treatment; Study 2: Nurse counseling of treated patients to encourage them to refer partners for treatment	Data: Partner services program data from an STI clinic Time period: 08/1985–12/1985	Setting: Indianapolis, Indiana Population: Study 1: Men and women at a county STI clinic with diagnosed chlamydial infection; Study 2: female sex partners of male STI clinic patients with nongonococcal urethritis Study 1: N=142 (76 women, 66 men); Study 2: N=678 male index patients
Kerani et al., 201141	Intervention: Patient-delivered partner therapy (PDPT) and a web-based partner notification service (inSPOT) with 3 treatments (PDPT, inSPOT, and combined PDPT/inSPOT) Infections: Gonorrhea, chlamydia	Design: Randomized controlled trial Comparator: Standard partner management	Data: Partner services program data; baseline and follow-up study interviews approximately 2 wk apart Time period: 07/2007–03/2009 (note: the trial ended early due to low enrollment)	Setting: King County, Washington Population: MSM with gonorrhea and chlamydia eligible for partner services, excluding MSM diagnosed with HIV or syphilis Sample: PDPT only, n=13; inSPOT only, n=10; PDPT/inSPOT combined, n=17; standard partner management (control), n=13 (among eligible MSM, 75 [19%] consented to the study and 53 [71%] of enrolled MSM completed the baseline and follow-up interviews)
Landis et al., 199228	Intervention: Partner notification by public health counselors Infection: HIV	Design: Randomized controlled trial Comparator: Partner notification by patients	Data: North Carolina HIV testing program data Time period: 11/1988–06/1990	Setting: 3 large county health departments in North Carolina Population: Clients with confirmed HIV infection identified through anonymous testing or confidential testing through the health departments, excluding individuals who previously tested positive for HIV or had no new sex or needle-sharing partners Sample: n=74 index patients and 310 partners (treatment group, n=39 index patients and 157 partners; control group: n=35 index patients and 153 partners); among those eligible for the study, 45.7% enrolled
Malave et al., 200829	Intervention: Partner notification provided by DIS in STI clinics Infection: HIV	Design: External control group Comparator: Partner notification delivered by community clinicians in non-STI clinics	Data: Provider report form from community clinicians and the NYC health department HIV surveillance registry Time period: 2004	Setting: 10 health department-run STI clinics and other diagnosing facilities (hospitals, clinics, and private physician offices) in NYC Population: Index patients diagnosed with HIV, excluding those diagnosed in health department-run TB clinics and NYC jail clinics Sample: n=3,666 (diagnosed in STI clinics, n=206; diagnosed in non-STI clinics, n=3,460)
Renaud et al., 201130	Intervention: Incorporating field testing into partner services Infection: HIV	Design: Pre-post design with no external control group Comparator: Pre-intervention period	Data: Partner services data, provider reports, partner-provided test results documents, medical records Time period: 09/2006–08/2007 (pre-intervention) versus 09/2008–08/2009 (intervention)	Setting: NYC Population: Sex and needle sharing partners of recently diagnosed HIV patients Sample: n=532 partners notified (pre-intervention period, n=181; intervention period, n=351)
Ronen et al., 201942	Interventions: Quarterly text message service for testing reminders to MSM with early syphilis and gonorrhea or chlamydia (note: the study includes a third group of MSM already enrolled in another reminder service, which we interpreted as a second treatment group because they were compared to the no-text message group) Infections: Chlamydia, gonorrhea, syphilis	Design: External control group (note: there were pre-intervention data but the comparison between groups is based on post-intervention data only) Comparator: MSM who did not accept the intervention and did not use text message reminders	Data: STI surveillance and partner service data Time period: 07/2013–01/2018	Setting: King County, Washington Population: Individuals identified as cis or trans male gender and who reported sex with men in the past year, had male sex partners recorded by their provider on the case report, and/or were diagnosed with rectal gonorrhea or rectal chlamydia Sample: n=3,376 (text message reminder accepted [treatment 1]: n=521; no text message reminder [comparator]: n=2,629; already enrolled in another reminder service [treatment 2]: n=226)
Rosenberg, 199743	Intervention: Social network analysis (SNA) interviews conducted by specially trained interviewers Infection: Syphilis	Design: External control group via a pre-post design (different interventions were delivered in the pre and post periods) Comparator: Traditional partner notification interview	Data: Partner notification and SNA interview data Time period: Partner notification, 01/01/1996–06/30/1996; SNA: 08/01/1996–01/31/1997	Setting: 4 contiguous parishes in Louisiana: Ascension, Iberville, East Baton Rouge, and West Baton Rouge Population: Partner notification index patients were primary and secondary (P&S) syphilis patients from the state surveillance database residing within the 4 parishes; SNA index patients were a convenience sample of P&S syphilis patients that had not yet received contact tracing or partner notification interviews Sample: n=88 index patients (partner notification, n=72; SNA, n=16) and 80 contacts from 10 of the 16 SNA index patient interviews
Schwebke & Desmond, 201044	Interventions: 1) Patient delivered partner therapy (PDPT) and 2) DIS interview and DIS-assisted partner notification and treatment Infection: Trichomoniasis	Design: Randomized controlled trial Comparator: Patient self-referral of partners (partner referral)	Data: Repeat laboratory specimens collected at the clinic and study questionnaires Time period: 02/2003–06/2008	Setting: Jefferson County health department STI clinic, Birmingham, Alabama Population: Adult women with Trichomonas vaginalis infection (primarystudy population), and their male partners Sample: n=484 women (PDPT, n=162; DIS, n=162; partner referral [control], n=160) and 115 male partners (70 enrolled from the DIS arm, 45 enrolled from the partner referral arm; information from the 143 males receiving PDPT medication were via self-report by the female index patients) (continued on next page)
Steiner et al., 200345	Intervention: Field-delivered therapy Infections: Chlamydia, gonorrhea	Design: Pre-post design with no external control group Comparator: Pre-intervention period	Data: San Francisco health department STI program Time period: 1998–2001 (note: the statistical test considered in our review is for the 1998 to 2000 comparison)	Setting: San Francisco, California Population: Persons diagnosed with uncomplicated chlamydial infection and/or gonorrhea who were unable or unlikely to come into the municipal STI clinic for treatment Sample: n=1,062 (pre-intervention: n=432 [1998]; post-intervention: n=630 [2000])
Taylor et al., 201046	Intervention: Placement of on-site or on-call DIS in 3 HIV clinics to deliver penicillin to patients and partners and conduct on-site partner elicitation interviews Infection: Syphilis	Design: Pre-post design with no external control group Comparator: Pre-intervention period	Data: STI surveillance data Time period: 01/2006–01/2008 (pre-intervention) versus 02/2008–09/2009 (post-intervention)	Setting: 3 HIV clinics in Maricopa County, Arizona Population: Patients diagnosed with syphilis Sample: n=334 (before DIS placement: n=219; after DIS placement: n=115)
Tributino et al., 201847	Intervention: Provision of on-site DIS-delivered partner notification services as part of standard clinic care at an STI clinic Infections: Gonorrhea, syphilis	Design: Pre-post design with no external control group Comparator: Pre-intervention period	Data: Medical records from the STI clinic Time period: 08/2014–12/2015, excluding the implementation month (04/2015)	Setting: 1 public health STI clinic, Providence, Rhode Island Population: Patients who received a diagnosis of gonorrhea or syphilis Sample: n=145 (pre-intervention: n=58; post-intervention: n=87)
Udeagu et al., 201231	Intervention: Partner services delivered in HIV clinics by placing DIS on-site in hospitals and community providers (Field Services Unit [FSU]-participating sites) Infection: HIV	Design: Pre-post design with external control group (note: authors compared pre-post outcome separately for the treatment and control groups) Comparator: Partner services delivered by community providers that did not have the collaboration with on-site DIS	Data: Partner service data (HIV FSU database; Provider Report Form database) Time period: 2005–2008	Setting: Multiple facilities in NYC (details not specified) Population: Newly diagnosed HIV patients Sample: n=2,695 (FSU participating sites: n=678 pre-intervention, n=602 post-intervention; non-participating sites: n=788 pre-intervention, n=635 post-intervention)
Udeagu et al., 201432	Intervention: Telephone partner services by the Field Services Unit Infection: HIV	Design: Pre-post design with external control group (note: the statistical analysis compared “post” outcomes between groups) Comparator: In-person partner services	Data: NYC Field Services Unit data Time period: 2009–2012	Setting: NYC Population: Sex partners named by HIV patients who had an interview with DIS and were HIV negative or with unknown HIV serostatus at notification Sample: n=3,604 (in-person notification: n=2,086; telephone notification: n=1,518)
Udeagu et al., 201433	Interventions: Internet-based partner services and text messaging partner services (2 interventions) Infection: HIV	Design: External control group Comparator: Traditional partner services using postal mail, telephone calls, and field visits	Data: NYC Field Services Unit partner services data Time period: 01/2011–10/2012	Setting: NYC Population: HIV-diagnosed patients and their partners named during partner services investigations Sample: n=3,319 partners named by 1,828 patients (traditional partner services [control]: 2,604 partners named by 1,596 index patients; internet-based partner services [treatment]: 275 partners named by 73 index patients; text message-based partner services: 368 partners named by 176 index patients)
Vest et al., 200752	Intervention: Provider partner notification via email for pseudonymous sex partners with email as the only contact information available Infections: HIV, syphilis	Design: External control group Comparator: Conventional method of partner notification, which uses contact information other than email addresses	Data: Austin/Travis County health department STI surveillance data Time period: 01/2004–06/2006	Setting: City of Austin and Travis County, Texas Population: Residents diagnosed with HIV and/or early syphilis who reported having sexual contact with pseudonymous email partners Sample: n=318 (treatment: n=53; control: n=265)
Woodhouse et al., 198548	Intervention: Interviewing diagnosed patients and contact tracing, with the military clinics under direction of a health department representative Infection: Gonorrhea	Design: External control group via a pre-post design (different interventions were delivered in the pre and post periods); results stratified by military versus civilian populations Comparator: Rotating medical personnel without specialized STI training providing patient interviewing or counseling without partner elicitation or field follow-up	Data: Patient interview records and STI surveillance data (note: data sources presumed and difficult to interpret due to older study year) Time period: 1977–1979 (pre-intervention) and 1980–1982 (intervention)	Setting: Colorado Springs, Colorado (military base and surrounding community) Population: Military and civilian gonorrhea patients and their contacts Sample: Military population, n=3,842 gonorrhea patients (pre: n=1,934, post: n=1,908) and n=4,450 contacts (pre: 1,341, post: 3,109); civilian population, n=5,253 gonorrhea patients (pre: n=2,919, post: n=2,334) and n=7,502 contacts (pre: 3,212, post: 4,290)

CDC, Centers for Disease Control and Prevention; DIS, disease intervention specialists; FSU, Field Service Unit; HIV, human immunodeficiency virus; ILOW, indigenous leadership outreach workers; MSM, men who have sex with men; NYC, New York City; PDPT, patient-delivered partner therapy; PWH, persons with HIV; STI, sexually transmitted infection; SNA, social network analysis; TB, tuberculosis.