a b s t r a c t

Background: To investigate the prevalence of undiagnosed HIV infections in an emergency department (ED) with an established screening program.

Methods: Evaluation of the prevalence and risk factors for HIV from an 8-week (June 24, 2007-August 18, 2007) identity-unlinked HIV serosurvey, conducted at the same time as an ongoing opt-in rapid oral-fluid HIV screen- ing program. Testing facilitators offering 24/7 bedside rapid testing to patients aged 18 to 64 years, with concor- dant collection of excess sera collected as part of routine clinical procedures. Known HIV positivity was determined by (1) medical record review or self-report from the screening program and/or (2) presence of antiretrovirals in serum specimens.

Results: Among 3207 patients, 1165 (36.3%) patients were offered an HIV test. Among those offered, 567 (48.7%) consented to testing. Concordance identity-unlinked study revealed that the prevalence of undiagnosed infec- tions was as follows: 2.3% in all patients, 1.0% in those offered testing vs 3.0% in those not offered testing (P b

.001); and 1.3% in those who declined testing compared with 0.4% in those who were tested (P = .077). Higher median viral loads were observed in those not offered testing (14255 copies/mL; interquartile range, 1147- 64354) vs those offered testing (1865 copies/mL; interquartile range, undetectable-21786), but the difference was not statistically significant.

Conclusions: high undiagnosed HIV prevalence was observed in ED patients who were not offered HIV testing and

those who declined testing, compared with those who were tested. This indicates that even with an intensive facilitator-based rapid HIV screening model, significant missed opportunities remain with regard to identifying unDiagnosed infections in the ED.

(C) 2015

? Funding sources: The study was supported by the Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health. Dr Kraus was supported by the 2007 Emergency Medicine Foundation/Society for Academic Emergen- cy Medicine Medical Student Research Grant to conduct the identity-unlinked seroprevalence study. The Johns Hopkins University Department of Emergency Medicine HIV Testing Pro- gram was funded in part by grants from Maryland Department of Health and Mental Hygiene. Dr Hsieh is also supported in part by a National Institutes of Health award, K01AI100681 from National Institute of Allergy and Infectious Diseases, to study HIV testing in emergency de- partments using a modeling approach. Dr Rothman is currently supported in part by funding from the Gilead Focus Program, which does not fund this project.

?? Declaration of interests: We declare no competing interests.

? Ethics committee approval: The Johns Hopkins University School of Medicine Institu-

tional Review Board approved the identity-unlinked seroprevalence study as well as the ED-based HIV testing and linkage to care program.

* Corresponding author at: Department of Emergency Medicine, Johns Hopkins Univer- sity, 5801 Smith Ave, Suite 3220 Davis Building, Baltimore, MD 21209. Tel.: +1 410 735

6413; fax: +1 410 735 6425.

E-mail address: [email protected] (Y.-H. Hsieh).

1. Introduction

The Centers for Disease Control and Prevention (CDC) estimates that 14% of 1.2 million HIV-infected individuals in the United States were un- aware of their positive serostatus [1]. Numerous previous studies have demonstrated that US emergency departments (EDs) are the leading sites of encounter for “late-testers” and the most common site of “missed opportunities” for HIV testing in medical settings [2,3]. In order to better understand the magnitude of the hidden epidemic, ED investigators pioneered identity unlinked seroprevalence methodolo- gies [4-7] and demonstrated high prevalence of unrecognized HIV in- fections, both historically and more recently. Since 2006, the CDC revised recommendations for HIV testing in health care settings [8], and numerous US EDs have established organized HIV testing programs to help find those with unrecognized HIV, with some success [9,10].

http://dx.doi.org/10.1016/j.ajem.2015.10.002

0735-6757/(C) 2015

Unfortunately, despite intensive national efforts, ED HIV Screening programs still fail to identify many infected patients. A recent blinded seroprevalence study, conducted in the context of an ongoing nontargeted counselor-based HIV testing program in one ED in Washington, DC, found that the prevalence of undiagnosed HIV infec- tion was 3 times higher among those who declined testing, as compared with those who accepted [11]. Notably, that study was conducted in a setting which used an opt-out approach for HIV screening (which in practice may not always be the norm [9], due to state regulations and/or pragmatic issues) and assessed seroprevalence only on the select subset of patients who were considered “eligible” to participate in opt- out screening, namely, those with nonurgent medical conditions, and were deemed able to communicate with “normal” mental status. Thus, gaps remain with regard to defining the full spectrum of potential missed opportunities for HIV testing in EDs (including a more compre- hensive assessment of demographic and clinical characteristics of those patients). Further study would be informative for optimizing strategies for HIV detection in ED settings.

Situated in a high HIV prevalence area in Baltimore City, our ED has implemented programmatic rapid HIV screening since 2005 [12]. During the summer of 2007, we conducted an identity-unlinked HIV seroprevalence study, simultaneous with 24/7 dedicated testing facilitator-based HIV testing. Our objectives were to (1) determine the prevalence of undiagnosed HIV infections in the context of an active dedicated testing facilitator driven HIV opt-in nontargeted screening program, and (2) define and compare characteristics of patients with undiagnosed HIV infections, among those who were offered (vs not offered) HIV testing, and among those among who did (vs did not) con- sent to having an HIV test performed.

1. Methods

Our study was conducted in an academic adult ED in Baltimore City, which in 2007 saw approximately 60000 visits annually. The ED serves an urban, inner-city population with a historically high HIV prevalence of 11% to 12% and an HIV incidence of 0.56% to 0.94% per year [6].

Our nontargeted, rapid, oral fluid (OraQuick Advanced, OraSure Technologies, Bethlehem, PA) opt-in HIV screening program aimed to offer free HIV testing to as many as possible ED patients who met the fol- lowing criteria: ages 18 to 64 years, not critically ill, no previous diagno- sis of HIV, no HIV test in the past 3 months, and able to provide informed consent. The operational model of screening program evolved over time based on the staffing model used and varied logistical considerations, in- cluding level of funding to support our supplementary staff [12]. In the summer of 2007 (concordant with the time that this study was carried out), the screening program operated with trained facilitators who of- fered HIV testing to eligible ED patients, 24 hours a day, 7 days a week. These facilitators performed abbreviated pretest and posttest counsel- ing, consent for HIV testing, and collected oral swab specimens which were tested in the ED satellite laboratory by dedicated laboratorians. One full-time dedicated HIV program coordinator was responsible for linkage to care for any newly diagnosed HIV-infected patients. Details of the testing program have been described elsewhere [12].

An identity-unlinked HIV seroprevalence study was carried out dur- ing the summer of 2007 (8-week duration). All ED patients 18 years or older who had Blood drawn for clinical purposes (and in whom excess sample was available for HIV testing) were included and evaluated using an identity-unlinked seroprevalence methodology [5]. Briefly, basic Demographic and clinical data including HIV relevant information were extracted prior to sample de-identification. De-identified samples were then tested for HIV by third-generation enzyme immunoassays (enzyme-linked immunosorbent assay); all positives were confirmed by Western blot followed by RNA viral load (VL) testing using Roche Amplicor v1.5, which has a limit of detection of 400 copies/mL (Roche, Indianapolis, IN). Antiretrovirals (ARVs) in serum specimens were de- tected using ultraperformance liquid chromatography-tandem mass

spectrometry by the Clinical Pharmacology Laboratory at our institution. Known HIV positivity was determined by (1) both medical record review and review of self-report from the HIV screening program (as applicable) and/or (2) presence of ARVs in serum specimens. The study was approved by the Johns Hopkins University School of Medicine Institutional Review Board. Use of an identity-unlinked methodology for determining HIV seroprevalence is permitted via a consent waiver [5,13] and involves accessing excess waste clinical blood specimens and paring that with de-identified demographic and administrative data, for purposes of understanding HIV epidemiology in the population.

Two-sided P b .05 was considered statistically significant. ?² Tests or Fisher exact tests were performed to determine prevalence ratio or rel- ative differences in proportion of undiagnosed HIV cases by their status in the screening program. Nonparametric Wilcoxon rank sum tests were performed to determine the differences in HIV RNA VLs by screen- ing program group using SAS version 9.3 (SAS Institute Inc, Cary, NC).

1. Results

During the 8-week study period, there were 9179 ED visits and 4475 serum specimens collected from 7254 unique patients. After excluding multiple specimens from the same visits and repeat visits, 3399 unique patients were included. After excluding 192 known positive patients, there were 3207 unique patients remaining, whom were included for the analysis. Among those patients, 1165 (36.3%) patients were offered an HIV test during their ED visits, whereas 2042 (63.7%) were not. Of those offered a test, 598 (51.3%) patients declined, whereas 567 (48.7%) accepted the test. There were 22 patients who accepted the test but were not tested, and another (ie, distinct group of) 22 patients who initially declined the test, but were later tested as part of their care in the ED. The overall prevalence of undiagnosed HIV infection was 2.3% (73/3207; Figure).

Significant differences were observed when comparing those who were offered HIV testing vs those who were not, with regard to age, sex, race, and payor type (Table 1). After excluding patients older than 64 years (ie, outside of 2006 CDC-recommended age group for HIV test- ing), age was not found to be significantly associated with whether a test was offered or not. Patients who were offered an HIV test were more likely to be African American but less likely to be publicly insured compared with those who were not offered an HIV test.

The prevalence of undiagnosed HIV was 3 times higher in those who were not offered vs those who were offered (3.0% vs 1.0%, respectively; prevalence ratio, 2.90; 95% confidence interval, 1.57-5.36; P b .001). Furthermore, after excluding those older than 64 years, the undiag- nosed prevalence of HIV was even higher at 3.8%, among those not offered testing. No statistically significant differences were observed with regard to age, sex, race, triage Acuity level, or medical insurance payor type among patients with undiagnosed HIV infection, according to whether or not they were offered a test (Table 2). However, a signif- icant difference was observed in the distribution of types of chief com- plaint when comparing those who were offered vs not offered, an HIV test (P = .004, Fisher exact test; Table 3).

Among those who were offered an HIV test, marginally significant differences in the prevalence of undiagnosed HIV infection were observed according to patient’s acceptance status. Eight (1.3%) of 576 patients who declined the testing (and were not tested) were HIV infected vs 2 (0.4%) of 545 patients who accepted and were tested for HIV (prevalence ratio, 3.79; 95% confidence interval, 0.81-17.74; P =

.077). Two (9.1%) of 22 patients who initially accepted the test (but

were ultimately not tested during their ED visit) and none of the 22 pa- tients who initially declined testing (but were later testing as part of their clinical care) were HIV infected.

The average mean HIV RNA VLs among the 73 undiagnosed HIV- infected patients was 110 340 copies/mL (range, undetectable- 3396395); the median VLs was 10814 copies/mL (interquartile range

3207 Patients with Blood Samples

73 (2.3%) HIV-Undiagnosed

8 (1.3%) – Undiagnosed

545 Tested

22 Not Tested

22 Patients Tested*

576 Not Tested

2 (0.4%) – Undiagnosed 2 (9.1%) -Undiagnosed 0 (0%) -Undiagnosed 8 (1.4%) – Undiagnosed

598 Initially Declined

567 Initially Accepted

4 (0.7%) – Undiagnosed

2042 Not Offered

61 (3.0%) -Undiagnosed

1165 Offered

12 (1.0%) – Undiagnosed

Figure. Proportion of undiagnosed HIV cases in urban emergency department patients in an identity-unlinked seroprevalence study by ED-based rapid HIV screening program status, 2007.

* Patients who were tested as part of their clinical care in the ED based on later requests by patients or providers outside of the initial ED screening program.

[IQR], 749-44660 copies/mL). Higher mean and median VLs were observed in those who were not offered (mean, 129005 +- 455391 copies/mL; median, 14255 copies/mL; IQR, 1147-64354 copies/mL) vs those who were offered (15 463 +- 29 226 copies/mL; median, 1865 copies/mL; IQR, undetectable-21786), but the difference was not statis- tically significant (P = .103, Wilcoxon rank sums test). Eighteen (25%) patients with undiagnosed HIV infection had VLs greater than 50000 copies/mL. Of these, 17 were not offered testing and only 1 was offered and tested by the program. There was no significant difference in pro- portion of patients with high HIV VLs (N 50000 copies/mL) by HIV test- ing offer status (not offered: 28% vs offered: 8%, P = .282).

1. Discussion

In our ED, which has a known historically high prevalence of HIV in- fections among its patients [5,6,12,14], we found a significantly higher prevalence of undiagnosed HIV among patients who were not offered HIV testing vs those who were offered, despite the existence of a

Table 1

Characteristics of ED patients by ED-based rapid HIV screening program status, 2007

concordant 24/7 dedicated testing facilitator-based opt-in rapid ED- based HIV screening program. Although the broad goals of our screen- ing program were to offer and test as many eligible patients as possible, our facilitator model resulted in only 36% of all patients (or 42% of the age eligible patients, ie, those b 65 years of age) being offered a test. Although those numbers seem relatively low, the percentage of HIV test offer is comparable to the average (39%) reported by other peer- reviewed studies [15]. The proportion (47%; 545/1165) of patients who were tested among those offered in our study was also comparable to the average (42%) reported [15]. Although we were unable to system- atically gather reasons for not offering an HIV test to patients, empiric observations indicate that reasons for nonoffer included presence of in- dividual patient exclusion criteria (ie, critically ill, unable to consent, pa- tient self-reported HIV testing history within previous 3 months, and known HIV positivity status), as well as the relative lack of personnel re- sources required to approach each potentially eligible patient. Recent published studies suggest that an integrated, streamlined, and automat- ic electronic opt-out approach, which can eliminate barriers associated with HIV testing offer, may minimize the observed discordance be- tween undiagnosed HIV infections and the underlying HIV seropreva- lence [16-18].

Of the total number of undiagnosed HIV-infected patients who came

Characteristics	Categories	HIV Screening			to our ED during the study period, 61 (84%) of 73 were not offered a test
		Offered	Not offered		for HIV. Notably, a significantly higher proportion of patients who were
		(n = 1165)	(n = 2042)
Age (y)?	18-24	153 (13)	225 (11)		Table 2
	25-34	214 (18)	328 (16)		Characteristics of 73 undiagnosed HIV-infected patients in an urban ED by ED-based rapid
	35-44	278 (24)	391 (19)		HIV screening program status, 2007
	45-54	279 (24)	398 (19)
	55-64	209 (18)	236 (12)		Characteristics Categories HIV Screening
	>= 65 Unknown	32 (3) 0 (0)	462 (23) 2 (0)		Offered Not offered (n = 12) (n = 61)
Sex	Female	658 (56)	1105 (54)
Male		507 (44)	937 (46)		Age (y)	18-24	0 (0)	1 (2)
Race? African American		817 (70)	1309 (64)			25-34	1 (8)	12 (20)
White		296 (25)	600 (29)			35-44	3 (25)	25 (41)
Hispanic		18 (2)	37 (2)			45-54	5 (42)	18 (30)
Other		25 (2)	72 (4)			55-64	2 (17)	4 (7)
Unknown		9 (1)	24 (1)			>= 65	1 (8)	1 (2)
triage acuity level? 1		27 (2)	140 (7)		Sex	Female	5 (42)	26 (43)
2		335 (29)	605 (30)			Male	7 (58)	35 (57)
3		701 (60)	1168 (57)		Race	African American	11 (92)	52 (85)
4		83 (7)	84 (4)			White	1 (8)	7 (11)
5		0 (0)	7 (0)			Other	0 (0)	1 (2)
Unknown		19 (2)	38 (2)			Unknown	0 (0)	1 (2)
Health Insurance? Public		179 (15)	527 (26)		Triage Acuity Level	1	0 (0)	4 (7)
Private		573 (49)	811 (40)			2	3 (25)	16 (26)
Self-pay		390 (33)	655 (32)			3	9 (75)	38 (62)
Other		23 (2)	49 (2)			4	0 (0)	3 (5)
Disposition? Admit		420 (36)	832 (41)			5	0 (0)	0 (0)
Discharged		687 (59)	1098 (54)		Health Insurance	Public	2 (17)	16 (26)
Against medical advice		30 (3)	36 (2)			Private	7 (58)	28 (46)
Left without being seen		7 (1)	22 (1)			Self-pay	3 (25)	16 (26)
Referral		2 (0)	12 (1)			Other	0 (0)	1 (2)
Expired		0 (0)	4 (0)		Disposition	Admit	4 (33)	31 (51)
Other		19 (2)	38 (2)			Discharged	6 (50)	29 (48)
* P b .05.						Against medical advice	2 (17)	1 (2)

Table 3

Chief complaints of ED visits by 73 undiagnosed hiv-infected patients in an urban adult ED, June-August 2007

Chief Complaints	No.	HIV screening		the prevalence ratio between 2 groups was approximately 4, which is
(n = 73) Offered Not offered comparable to that in an ED testing program in Washington, DC [11]. (n = 12) (n = 61) Systematic destigmatization of HIV testing and reduction of testing bar-
Pain Altered mental/psychiatric	15 (21) 13 (18)	1 (8) 0 (0)	14 (23) 13 (21)	riers approach, for example, routine opt-out testing [16], would likely lower the prevalence ratio of undiagnosed infection, between those
Fever/sore throat/vomiting/	13 (18)	1 (8)	12 (20)	tested and those not tested. Alternatively, novel approaches to increase

offered testing in our study, we observed only a marginally statistically significant difference in the prevalence of undiagnosed HIV infection be- tween those who declined and those who accepted testing. However,

abscess/other infectious disease-related

Chest pain/short of breath	11 (15)	4 (33)	7 (12)
Injury/accident	6 (8)	0 (0)	6 (10)
Headache/migraine	4 (5)	3 (25)	1 (2)
Dizziness/syncope	2 (3)	1 (8)	1 (2)
Weakness/numbness	3 (4)	1 (8)	2 (3)
Other	6 (8)	1 (8)	5 (8)

P b .05, Fisher exact test, for the distribution of chief complaint category by HIV screening offered status.

not offered an HIV test were admitted to the hospital than those who were offered. In addition, most undiagnosed HIV-infected patients who were not offered an HIV test were admitted. Approximately 75% (45/61) of undiagnosed HIV-infected patients who were not offered an HIV test had chief complaint which included infectious disease- related conditions, pain, injury/accidents, or altered mental status/ psychiatric-related conditions, whereas only 17% (2/12) of those who were offered had one of these chief complaints. This suggests that those with undiagnosed infections in our ED were more likely to be those with critical illness and/or were conditions that precluded our fa- cilitators from providing informed consent (based on our program criteria from being eligible to approach). It is possible that our facilita- tors were overconservative with regard to interpreting eligibility criteria. Opt-out approaches for HIV test (at the point of triage and by the clinical staff) could help overcome at least some of those gaps. Alter- natively, addition of scaled-up routine inpatient screening programs for all ED admitted patients could minimize potential missed ED opportuni- ty for identifying those with undiagnosed infections [19]. In our own ED, that could have resulted in an additional 31 undiagnosed infections (or 51% of the total undiagnosed who were not offered) being detected. Based on use of identity-unlinked methodology used here, we are unable to know whether those individuals were diagnosed or not in our inpatient setting. However, previous studies from our own site and others suggest shortfalls and opportunities remain [20,21]. There were some additional observations based on chief complaints, with re- gard to whether patients with undiagnosed HIV were offered an HIV test or not (ie, those with chief complaints including chest pain/short of breath, headache/migraine, and dizziness/syncope had a relatively higher chance of being offered an HIV test than did those who presented with infectious diseases, pain, injury, and/or altered mental status- related chief complaints). Although it is impossible to say with certainty why this trend exists, one possible explanation is that certain chief complaints make it more likely that test facilitators can interact with the patients over the course of their ED stay (eg, those patients with headache or dizziness may clinically improve during their stay, and those with chest pain/short of breath may have longer lengths of stay [eg, in observation areas]), providing opportunities for screening en- counter with HIV testing facilitators.

Our findings are consistent with what has been previously described

in the literature; that is, there are significant proportions of ED patients who decline HIV testing despite being offered testing, and particularly when opt-in approaches are used [22]. Furthermore, among those who decline testing, our findings are consistent with what we and others have previously reported, namely, that among those who decline testing, there are a significantly higher prevalence of patients with tra- ditional “high-risk” behaviors [23] and a higher prevalence of undiag- nosed (or hidden) infections [11]. Of note, because of the relatively small number of undiagnosed infections in those patients who were

test acceptance, such as computerized registration/triage kiosks, could be considered and scaled-up, as they have already been shown to in- crease proportions of HIV test acceptance, both overall and among high-risk patients [23]. Such approaches could be particularly important in states where opt-out approaches for HIV testing are not yet permitted by state law.

During the 8-week study period, our screening program only detect- ed 2.7% (2/73) of the undiagnosed HIV-infected population who passed through our ED. Two individuals were offered testing, but ultimately not tested during their ED stay. There are multiple possible explanations for what might have occurred with those patients, including that the pa- tient decided to leave the ED prior to their test being performed, or they disclosed that they were HIV positive to the facilitator, after agree- ing to a test, and were not repeat tested (a known phenomenon we have recurrently observed in our ED). As noted above, due to the identity-unlinked nature of this study, we are unable to determine the definitive reason for those cases where testing did not occur. The re- maining 69 undiagnosed patients were either not offered a test or of- fered but declined. Despite the observed lack of statistical significance, there was a trend toward higher mean and median VLs and a higher proportion of high VLs (N 50000 copies/mL) in those who were not of- fered an HIV test vs those who were offered. This is a particularly impor- tant finding with regard to defining strategies to bridge the observed gaps, because HIV VL is known to be one of the most important predic- tors for HIV transmission [24]. Specifically, the rate of HIV transmission via sexual transmission is 9.03 per 100 person-years for those with a VL greater than 50000 copies/mL [25]. In addition, estimates suggest that approximately 8 HIV infections could be averted per 100 persons who were aware of their infection (vs those who were unaware) in a year [26]. Thus, from our study, 17 ED patients who had undiagnosed HIV infection and high VLs would likely generate approximately 2 new in- fections per year if they remained “hidden,” further driving the local HIV epidemic.

Our study is susceptible to several limitations. First, we may have underestimated known HIV positivity status because this was coded based solely our institutional electronic medical record (EMR) review and self-report. Patients might have been diagnosed as having HIV in other settings or testing venue, but their infection status may not have been documented in our hospital EMR. Patients could also choose not to disclose their HIV positivity status to the testing staff. To offset this potential misclassification bias and minimize our underestimate of “known” HIV, we did include laboratory test to detect the presence of ARVs; however, that would only pertain to those who were on therapy so potential biases remain. Second, our estimates cannot be generalized to our entire ED population due to selection bias. The study period was restricted to an 8-week period for one summer, and the study was also restricted to those with blood specimens, thus including only about 7% of annual ED visits. Annual data as well as seasonal trend regarding un- diagnosed HIV infection in our population are not available. Those with blood specimens were likely to be older or female but less likely to be African American, as compared with those without (data not shown). Therefore, the prevalence in those without blood specimens (young African American men) could likely be higher according to the data from our previous seroprevalence studies and local HIV epidemic in Bal- timore City. However, the true undiagnosed HIV prevalence remains unknown for those patients who did not have blood drawn. Third, our study was also reliant on the availability of waste blood specimens.

We believe that any potential biases associated with that were relatively small; however, because nearly all patients in our ED (based on our ob- served experience) who have blood drawn have sufficient excess serum for HIV testing in the identity-unlinked study. Fourth, new EMR tech- nologies (eg, electronic prompt from triage) and HIV diagnostic methods (ie, fourth-generation enzyme-linked immunosorbent assay) have been introduced into our ED in 2013. Furthermore, the current staffing and operational model for HIV testing in our ED (ie, triage- integrated nurse-driven HIV testing) [27] has significantly changed from what we describe herein from 2007 (ie, 24/7 dedicated facilitator-based HIV testing). It is thus possible that the high rates of un- diagnosed HIV observed here (among those not offered an HIV test) may not be present with our current screening program; future re- search will be required to address that. Nevertheless, our findings re- garding missed opportunities are important for those EDs that continue to provide HIV screening via a parallel facilitator-based model. Finally, our findings cannot be generalized to other EDs in the United States. Accordingly, results should be interpreted with caution because local HIV epidemic and ED-based HIV screening program might be different from ours.

In conclusion, we observed a disproportionately high prevalence of undiagnosed HIV infection in ED patients among patients who were not offered HIV screening and in those who declined screening vs those who accepted testing. This indicates that even with an intensive opt-in testing facilitator-based rapid HIV screening model, significant missed opportunities remain with regard to identifying undiagnosed HIV-infected individuals in the ED. These findings provide Conceptual framework and model for exploring the effectiveness of ED-based HIV screening programs. Opt-out, clinical staff-driven, registration/triage- based integrated Routine HIV testing models that help to de-stigmatize HIV by offering testing to every eligible patient are being evaluated cur- rently [16,17] and have already been shown to increase HIV test offer and test acceptance, to be expected helping curtail the missed opportu- nities we observed in this study.

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