Comparison of HIV Screening Strategies in the Emergency Department: A Randomized Clinical Trial.

Importance: The National HIV Strategic Plan for the US recommends HIV screening in emergency departments (EDs). The most effective approach to ED-based HIV screening remains unknown. Objective: To compare strategies for HIV screening when integrated into usual ED practice. Design, Setting, and Participants: This randomized clinical trial included patients visiting EDs at 4 US urban hospitals between April 2014 and January 2016. Patients included were ages 16 years or older, not critically ill or mentally altered, not known to have an HIV positive status, and with an anticipated length of stay 30 minutes or longer. Data were analyzed through March 2021. Interventions: Consecutive patients underwent concealed randomization to either nontargeted screening, enhanced targeted screening using a quantitative HIV risk prediction tool, or traditional targeted screening as adapted from the Centers for Disease Control and Prevention. Screening was integrated into clinical practice using opt-out consent and fourth-generation antigen-antibody assays. Main Outcomes and Measures: New HIV diagnoses using intention-to-treat analysis, absolute differences, and risk ratios (RRs). Results: A total of 76 561 patient visits were randomized; median (interquartile range) age was 40 (28-54) years, 34 807 patients (51.2%) were women, and 26 776 (39.4%) were Black, 22 131 (32.6%) non-Hispanic White, and 14 542 (21.4%) Hispanic. A total of 25 469 were randomized to nontargeted screening; 25 453, enhanced targeted screening; and 25 639, traditional targeted screening. Of the nontargeted group, 6744 participants (26.5%) completed testing and 10 (0.15%) were newly diagnosed; of the enhanced targeted group, 13 883 participants (54.5%) met risk criteria, 4488 (32.3%) completed testing, and 7 (0.16%) were newly diagnosed; and of the traditional targeted group, 7099 participants (27.7%) met risk criteria, 3173 (44.7%) completed testing, and 7 (0.22%) were newly diagnosed. When compared with nontargeted screening, targeted strategies were not associated with a higher rate of new diagnoses (enhanced targeted and traditional targeted combined: difference, -0.01%; 95% CI, -0.04% to 0.02%; RR, 0.7; 95% CI, 0.30 to 1.56; P = .38; and enhanced targeted only: difference, -0.01%; 95% CI, -0.04% to 0.02%; RR, 0.70; 95% CI, 0.27 to 1.84; P = .47). Conclusions and Relevance: Targeted HIV screening was not superior to nontargeted HIV screening in the ED. Nontargeted screening resulted in significantly more tests performed, although all strategies identified relatively low numbers of new HIV diagnoses. Trial Registration: ClinicalTrials.gov Identifier: NCT01781949.

Clarifying the volume of estimated need for public health and prevention services within an emergency department population.

OBJECTIVES: Emergency departments (EDs) are called to implement public health and prevention initiatives, such as infectious disease screening. The perception that ED resources are insufficient is a primary barrier. Resource needs are generally conceptualized in terms of total number of ED encounters, without formal calculation of the number of encounters for which a service is required. We illustrate potential differences in the estimated volume of service need relative to ED census using the examples of HIV and hepatitis C (HCV) screening. METHODS: This cross-sectional analysis adjusted the proportion of ED encounters in which patients are eligible for HIV and HCV screening according to a cascade of successively more restrictive patient selection criteria, presuming full implementation of each criterion. Parameter estimates for the proportion satisfying each selection criterion were derived from the electronic health records of an urban academic facility and its ED HIV and HCV screening program during 2 time periods. The primary outcome was the estimated reduction in proportion of ED visits eligible for screening after application of the entire cascade. RESULTS: There were 76,104 ED encounters during the study period. Applying all selection criteria reduced the number of required screens by 97.1% (95% confidence interval, 97.0-97.2) for HIV and 86.1% (95% confidence interval, 85.9-86.3) for HCV. CONCLUSIONS: Using the example of HIV and HCV screening, the application of eligibility metrics reduces the volume of service need to a smaller, more feasible number than estimates from ED census alone. This approach might be useful for clarifying perceived service need and guiding operational planning.

Identifying ED patients with previous abnormal HIV or hepatitis C test results who may require additional services.

OBJECTIVES: Routine emergency department (ED) HIV or HCV screening may inadvertently capture patients already diagnosed but does not specifically prioritize identification of this group. Our objective was to preliminarily estimate the volume of this distinct group in our ED population through a pilot electronic health record (EHR) build that identified all patients with indications of HIV or HCV in their EHR at time of ED presentation. METHODS: Cross-sectional study of an urban, academic ED's HIV/HCV program for previously diagnosed patients August 2017-July 2018. Prevention program staff, alerted by the EHR, reviewed records and interviewed patients to determine if confirmatory testing or linkage to care was needed. Primary outcome was total proportion of ED patients for whom the EHR generated an alert. Secondary outcome was the proportion of patients assessed by program staff who required confirmatory testing or linkage to HIV/HCV medical care. RESULTS: There were 65,374 ED encounters with 5238 (8.0%, 95% CI: 7.8%-8.2%) EHR alerts. Of these, 3741 were assessed by program staff, with 798 (21%, 95% CI: 20%-23%) requiring HIV/HCV confirmatory testing or linkage to care services, 163 (20%) for HIV, 551 (69%) for HCV, and 84 (11%) for both HIV and HCV services. CONCLUSIONS: Patients with existing indication of HIV or HCV infection in need of confirmatory testing or linkage to care were common in this ED. EDs should prioritize identifying this population, outside of routine screening, and intervene similarly regardless of whether the patient is newly or previously diagnosed.

Exploring Current Stereotypes and Norms Impacting Sexual Partner HIV-Status Communication.

This study sought to explore HIV-related stereotypes and norms that impact HIV-status communication with potential sexual partners. A series of focus groups and in-depth interviews were conducted (N = 59) with HIV-positive and HIV-negative MSM (75%) and Heterosexuals (25%). Findings indicate that HIV stereotypes and stigma remain as barriers to HIV-status discussion. Differences also emerged across groups: 1) HIV-negative MSM were more likely to report engaging in HIV-status communication, 2) HIV-positive MSM described inconsistent HIV-status communication and reported concealing their status at times, and 3) Heterosexuals reported being least likely to engage in HIV-status communication; often using the blanket question "Are you clean?" to encompass all STIs and avoiding direct HIV-status discussion. Overall, findings indicate that many HIV stereotypes and stigma-related communication norms persist that discourage discussion of sexual partners' HIV-status prior to sexual activity.

Pilot Integration of HIV Screening and Healthcare Settings with Multi- Component Social Network and Partner Testing for HIV Detection.

BACKGROUND: Healthcare settings screen broadly for HIV. Public health settings use social network and partner testing ("Transmission Network Targeting (TNT)") to select high-risk individuals based on their contacts. HIV screening and TNT systems are not integrated, and healthcare settings have not implemented TNT. OBJECTIVE: The study aimed to evaluate pilot implementation of multi-component, multi-venue TNT in conjunction with HIV screening by a healthcare setting. METHODS: Our urban, academic health center implemented a TNT program in collaboration with the local health department for five months during 2011. High-risk or HIV positive patients of the infectious diseases clinic and emergency department HIV screening program were recruited to access social and partner networks via compensated peer-referral, testing of companions present with them, and partner notification services. Contacts became the next-generation index cases in a snowball recruitment strategy. RESULTS: The pilot TNT program yielded 485 HIV tests for 482 individuals through eight generations of recruitment with five (1.0%; 95% CI = 0.4%, 2.3%) new diagnoses. Of these, 246 (51.0%; 95% CI = 46.6%, 55.5%) reported that they had not been tested for HIV within the last 12 months and 383 (79.5%; 95% CI = 75.7%, 82.9%) had not been tested by the existing ED screening program within the last five years. CONCLUSION: TNT complements population screening by more directly targeting high-risk individuals and by expanding the population receiving testing. Information from existing healthcare services could be used to seed TNT programs, or TNT could be implemented within healthcare settings. Research evaluating multi-component, multi-venue HIV detection is necessary to maximize complementary approaches while minimizing redundancy.

The Know∗Now Project: Facilitated Serosorting in HIV-Status Sexual Partner Communication.

An intervention was conducted providing access to clinic-verified HIV test results via a secure, web-based informatics platform to facilitate sexual partner HIV-status communication. Participants (N = 28) were men who have sex with men (MSM; HIV- n = 8, HIV+ n = 8) and heterosexuals (Non-MSM, n = 12). Focus groups with same-group members explored interest in using the intervention and baseline attitudes and practices relevant to serosorting. HIV-negative participants overwhelmingly expressed interest, regardless of MSM status. Interest among HIV-positive MSM was mixed. Six month follow-up interviews (n = 16) indicated 94% of all groups accessed the website, 69% had shown documented results to a sexual partner to initiate HIV-status discussion, and 88% reported future interest in using the 24/7 web-based tool with prospective sexual partners. Implications for future interventions facilitating HIV serosorting and sexual partner communication are discussed.

Emergency Department Prescription Opioids as an Initial Exposure Preceding Addiction.

STUDY OBJECTIVE: Opioid abuse and overdose constitute an ongoing health emergency. Many presume opioids have little potential for iatrogenic addiction when used as directed, particularly in short courses, as is typical of the emergency department (ED) setting. We preliminarily explore the possibility that initial exposure to opioids by EDs could be related to subsequent opioid misuse. METHODS: This cross-sectional study surveyed a convenience sample of patients reporting heroin or nonmedical opioid use at an urban, academic ED. We estimated the proportion whose initial exposure to opioids was a legitimate medical prescription and the proportion of those prescriptions that came from an ED. Secondary measurements included the proportion of patients receiving nonopioid substances before initial opioid exposure, the source of opioids between initial exposure and onset of regular nonmedical use, and time from initial prescription to opioid use disorder. RESULTS: Of 59 subjects, 35 (59%; 95% confidence interval [CI] 47% to 71%) reported they were first exposed to opioids by a legitimate medical prescription, and for 10 of 35 (29%; 95% CI 16% to 45%), the prescription came from an ED. Most medically exposed subjects (28/35; 80%; 95% CI 65% to 91%) reported nonopioid substance use or treatment for nonopioid substance use disorders preceding the initial opioid exposure. Emergency providers were a source of opioids between exposure and onset of regular nonmedical use in 11 of 35 cases (31%; 95% CI 18% to 48%). Thirty-one of the 35 medically exposed subjects reported the time of onset of nonmedical use; median time from exposure to onset of nonmedical use was 6 months for use to get high (N=25; interquartile range [IQR] 2 to 36), 12 months for regular use to get high (N=24; IQR 2 to 36), 18 months for use to avoid withdrawal (N=26; IQR 2 to 38), and 24 months for regular use to avoid withdrawal (N=27; IQR 2 to 48). Eleven subjects (36%; 95% CI 21% to 53%) began nonmedical use within 2 months, and 9 of 11 (82%; 95% CI 53% to 96%) reported nonopioid substance use or treatment for alcohol abuse before initial opioid exposure. CONCLUSION: Although short-term opioid administration by emergency providers is unlikely to cause addiction by itself, ED opioid prescriptions may contribute to the development of addiction in some patients. There is an urgent need for further research to estimate long-term risks of short-course opioid therapy so that the risk of iatrogenic addiction can be appropriately balanced with the benefit of analgesia.

Opportunities for earlier HIV diagnosis in a pediatric ED.

OBJECTIVES: Emergency department (ED) HIV screening is recommended but challenging to implement and of uncertain effectiveness in pediatric EDs (PEDs). We sought to determine whether there were opportunities for earlier HIV diagnosis in the PED for a cohort of young adults diagnosed with HIV. METHODS: This retrospective cohort study reviewed PED records of a group of young adults receiving HIV care in an urban hospital setting. Pediatric ED visits were selected for review if they took place after the patient's estimated time of HIV acquisition and before their eventual diagnosis. Charts were reviewed to determine whether HIV infection was suspected and whether testing was offered. RESULTS: Among a cohort of HIV-positive young adults, only 3 (3.6%; 95% confidence interval, 0.9-10.8) of 84 were seen in the PED during the time they were undiagnosed but likely to be infected with HIV. Among these subjects, there was no documentation that HIV testing was offered or refused nor was there documented suspicion of HIV. CONCLUSIONS: There are opportunities for earlier diagnosis of HIV in PEDs, affirming the importance of HIV screening implementation in these settings. However, PEDs are unlikely to have the same frequency of contact with undiagnosed individuals as do adult EDs. Alternative methods of accessing at-risk adolescent populations must be identified.

Prevalence of undiagnosed acute and chronic HIV in a lower-prevalence urban emergency department.

OBJECTIVES: We estimated the seroprevalence of both acute and chronic HIV infection by using a random sample of emergency department (ED) patients from a region of the United States with low-to-moderate HIV prevalence. METHODS: This cross-sectional seroprevalence study consecutively enrolled patients aged 18 to 64 years within randomly selected sampling blocks in a Midwestern urban ED in a region of lower HIV prevalence in 2008 to 2009. Participants were compensated for providing a blood sample and health information. After de-identification, we assayed samples for HIV antibody and nucleic acid. RESULTS: There were 926 participants who consented and enrolled. Overall, prevalence of undiagnosed HIV was 0.76% (95% confidence interval [CI] = 0.30%, 1.56%). Three participants (0.32%; 95% CI = 0.09%, 0.86%) were nucleic acid-positive but antibody-negative and 4 (0.43%; 95% CI = 0.15%, 1.02%) were antibody-positive. CONCLUSIONS: Even when the absolute prevalence is low, a considerable proportion of undetected HIV cases in an ED population are acute. Identification of acute HIV in ED settings should receive increased priority.

Patient perception of whether an HIV test was provided during the emergency department encounter.

This cross-sectional study approached emergency department (ED) patients after the treating physician's disposition decision to measure patient understanding of whether or not they had received an HIV test during their ED encounter. Of the 300 respondents, 24 were excluded due to missing data or because they had received an ED HIV test. Mean age was 41 years, 51% were men, 61% were black, and 29% had no high school degree. There were 5.8% (95% confidence interval: 3.5%-9.4%) who erroneously reported HIV test delivery during their ED course. Our results suggest a small but significant minority of patients falsely assume that they have been tested for HIV during their ED visit. This misperception could have broad implications, leading to less frequent subsequent testing, false reassurance of HIV-negative status, and inaccuracies in surveillance estimates or surveys that depend on self-report.

Randomized comparison of universal and targeted HIV screening in the emergency department.

OBJECTIVE: Universal HIV screening is recommended but challenging to implement. Selectively targeting those at risk is thought to miss cases, but previous studies are limited by narrow risk criteria, incomplete implementation, and absence of direct comparisons. We hypothesized that targeted HIV screening, when fully implemented and using maximally broad risk criteria, could detect nearly as many cases as universal screening with many fewer tests. METHODS: This single-center cluster-randomized trial compared universal and targeted patient selection for HIV screening in a lower prevalence urban emergency department. Patients were excluded for age (<18 and >64 years), known HIV infection, or previous approach for HIV testing that day. Targeted screening was offered for any risk indicator identified from charts, staff referral, or self-disclosure. Universal screening was offered regardless of risk. Baseline seroprevalence was estimated from consecutive deidentified blood samples. RESULTS: There were 9572 eligible visits during which the patient was approached. For universal screening, 40.8% (1915/4692) consented with 6 being newly diagnosed [0.31%, 95% confidence interval (CI): 0.13% to 0.65%]. For targeted screening, 37% (1813/4880) had no testing indication. Of the 3067 remaining, 47.4% (1454) consented with 3 being newly diagnosed (0.22%, 95% CI: 0.06% to 0.55%). Estimated seroprevalence was 0.36% (95% CI: 0.16% to 0.70%). Targeted screening had a higher proportion consenting (47.4% vs. 40.8%, P < 0.002), but a lower proportion of ED encounters with testing (29.7% vs. 40.7%, P < 0.002). CONCLUSIONS: Targeted screening, even when fully implemented with maximally permissive selection, offered no important increase in positivity rate or decrease in tests performed. Universal screening diagnosed more cases, because more were tested, despite a modestly lower consent rate.

Preliminary program evaluation of emergency department HIV prevention counseling.

OBJECTIVE: Controversy surrounds the linkage of prevention counseling with emergency department (ED)-based HIV testing. Further, the effectiveness and feasibility of prevention counseling in the ED setting is unknown. We investigate these issues by conducting a preliminarily exploration of several related aspects of our ED's HIV prevention counseling and testing program. METHODS: Our urban, academic ED provides formal client-centered prevention counseling in conjunction with HIV testing. Five descriptive, exploratory observations were conducted, involving surveys and analysis of electronic medical records and programmatic data focused on (1) patient perception and feasibility of prevention counseling in the ED, (2) patient perceptions of the need to link prevention counseling with testing, and (3) potential effectiveness of providing prevention counseling in conjunction with ED-based HIV testing. RESULTS: Of 110 ED patients surveyed after prevention counseling and testing, 98% believed privacy was adequate, and 97% reported that their questions were answered. Patients stated that counseling would lead to improved health (80%), behavioral changes (72%), follow-up testing (77%), and discussion with partners (74%). However, 89% would accept testing without counseling, 32% were willing to seek counseling elsewhere, and 26% preferred not to receive the counseling. Correct responses to a 16-question knowledge quiz increased by 1.6 after counseling (95% confidence interval 1.3 to 12.0). The program completed counseling for 97% of patients tested; however, 6% of patients had difficulty recalling the encounter and 13% denied received testing. Among patients undergoing repeated testing, there was no consistent change in self-reported risk behaviors. CONCLUSION: Participants in the ED prevention counseling and testing program considered counseling acceptable and useful, though not required. Given adequate resources, prevention counseling can be provided in the ED, but it is unlikely that all patients benefit.

Effect of an emergency department HIV testing program on the proportion of emergency department patients who have been tested.

OBJECTIVE: The lack of well-described population-level outcome measures for emergency department (ED) HIV testing is one barrier to translation of screening into practice. We demonstrate the impact of an ED diagnostic testing and targeted screening program on the proportion of ED patients ever tested for HIV and explore cumulative effects on testing rates over time. METHODS: Data were extracted from electronic HIV testing program records and administrative hospital databases for January 2003 to December 2008 to obtain the monthly number of ED visits and HIV tests. We calculated the proportions of (1) patients tested in the program who reported a previous HIV test or had been previously tested in the program, and (2) the cumulative number of unique ED patients who were tested in our program. RESULTS: During the study period, 165,665 unique patients made 491,552 ED visits and the program provided 13,509 tests to 11,503 unique patients. From 2003 to 2008, tested patients who reported a history of an HIV test increased by 0.085% per month (95% confidence interval [CI] 0.037% to 0.133%), from 67.7% to 74.4%; the percentage of tested patients who had previous testing in the program increased by 0.277% per month (95% CI 0.245% to 0.308%), from 3.2% to 21.2%; and the percentage of unique ED patients previously tested in the program increased by 0.100% per month (95% CI 0.096% to 0.105%), reaching a cumulative proportion of 6.9%. CONCLUSION: Our HIV testing program increased the proportion of ED patients who have been tested for HIV at least once and repeatedly tested a subset of individuals. HIV screening, even during a minority of ED visits, can have important cumulative effects over time.

Comparison of missed opportunities for earlier HIV diagnosis in 3 geographically proximate emergency departments.

OBJECTIVE: Differences in the prevalence of undiagnosed HIV between different types of emergency departments (EDs) are not well understood. We seek to define missed opportunities for HIV diagnosis within 3 geographically proximate EDs serving different patient populations in a single metropolitan area. METHODS: For an urban academic, an urban community, and a suburban community ED located within 10 miles of one another, we reviewed visit records for a cohort of patients who received a new diagnosis of HIV between July 1999 and June 2003. Missed opportunities for earlier HIV diagnosis were defined as ED visits in the year before diagnosis, during which there was no documented ED HIV testing offer or test. Outcomes were the number of missed opportunity visits and the number of patients with a missed opportunity for each ED. We secondarily reviewed medical records for missed opportunity encounters, using an extensive list of indications that might conceivably trigger testing. RESULTS: Among 276 patients with a new HIV diagnosis, 123 (44.5%) visited an ED in the year before diagnosis or received a diagnosis in the ED. The urban academic ED HIV testing program diagnosed 23 (8.3%) cases and offered testing to 24 (8.7%) patients who declined. Missed opportunities occurred during 187 visits made by 76 (27.5%) patients. These included 70 patients with 157 visits at the urban academic ED, 9 patients with 24 visits at the urban community ED, and 4 patients with 6 visits at the suburban community ED. Medical records were available for 172 of the 187 missed opportunity visits. Visits were characterized by the following potential testing indicators: HIV risk factors (58; 34%), related diagnosis indicating risk (7; 4%), AIDS-defining illness (8; 5%), physician suspicion of HIV (29; 17%), and nonspecific signs or symptoms of illness potentially consistent with HIV (126; 73%). CONCLUSION: Geographically proximate EDs differ in their opportunities for earlier HIV diagnosis, but all 3 sites had missed opportunities. Many ED patients with undiagnosed HIV have potential indications for testing documented even in the absence of a dedicated risk assessment, although most of these are nonspecific signs or symptoms of illness that may not be clinically useful selection criteria.

Risk, reasons for refusal, and impact of counseling on consent among ED patients declining HIV screening.

Screening for HIV in the emergency department (ED) is recommended by the Centers for Disease Control and Prevention. The relative importance of efforts to increase consent among those who currently decline screening is not well understood. We compared the risk characteristics reported by patients who decline risk-targeted, opt-in ED screening with those who consent. We secondarily recorded reasons for declining testing and reversal of the decision to decline testing after prevention counseling. Of 199 eligible patients, 106 consented to testing and 93 declined. Of those declining, 60 (64.5%) of 93 completed a risk assessment. There were no differences in HIV risk behaviors between groups. Declining patients reported recent testing in 73.3% of cases. After prevention counseling, 4 (6.7%) of 60 who initially declined asked to be tested. Given similarities between those who decline and those who consent to testing, efforts to increase consent may be beneficial. However, this should be tempered by the finding that many declined because of a recent negative test. Emphasizing risk during prevention counseling is not a promising strategy for improving opt-in consent rates.

Relationship of self-reported prior testing history to undiagnosed HIV positivity and HIV risk.

Screening everyone for HIV at least once is estimated to be cost-effective. Screening in health care settings is recommended to help achieve that goal. Health care settings often encounter the same patient repeatedly, and it is unknown if limited resources are better allocated to conduct repeat screening, or to screen patients not yet tested. We reviewed data for a targeted ED based HIV screening program for 2003-2007. The role of prior testing history as a predictor of undiagnosed HIV positivity was assessed using a negative binomial model adjusted for demographics and risk behaviors. HIV testing was provided to 8,450 unique patients. There were 5,781 (70%) self-reporting a prior HIV test. Compared with patients reporting no prior test, the relative risk of HIV positivity for those reporting a test within the prior year was 0.90 (95%CI 0.48-1.66), and for those reporting a prior test more than a year previously the relative risk was 0.91 (95%CI 0.48-1.73). Among patients testing positive, those who did not report a prior test had a median CD4 count that was 228 cells/mm(3) lower than those with a prior test (CI(95) of the difference in medians 20-436 cells/mm(3)). Diagnosis of prevalent HIV among those who are at risk but have never been tested should be a priority. However, repeat screening of target populations for incident infection remains important and results in earlier diagnosis. Recent self-reported testing history is not associated with undiagnosed positivity among targeted patients irrespective of the timing of the prior test.

Comparison of emergency department HIV testing data with visit or patient as the unit of analysis.

OBJECTIVES: Outcomes in an episodic care setting like an emergency department (ED) are traditionally evaluated in comparison with the number of visits as opposed to the number of unique patients, although patients commonly present to the ED multiple times. We examined the differences in HIV screening programme outcomes that would occur if the analysis were conducted at the patient-level, rather than the traditional visit-level. We hypothesized that while our ED-based HIV screening programme does test some patients repeatedly, the primary programme outcome of percent positive is not substantially altered by the unit of analysis. METHODS: We reviewed the clinical database of an ED HIV screening programme at a large, urban, teaching hospital in the United States from 2003-2007. Data were analyzed descriptively. The main outcome measure was the rate of positive test results computed with either the visit or the patient as the unit of analysis. RESULTS: HIV testing was provided at 9629 visits, representing 8450 unique patients. For patient-level analysis, the proportion of patients found to be positive was 0.91%. For visit-level analysis, the proportion of tests with positive results was 0.83%. Of the 910 patients with repeat testing, 7 (0.77%) were identified as positive at a repeat test. The median time between tests was 383 days (range 1-1742). CONCLUSIONS: Results changed little regardless of whether unique patients or unique visits were used as the unit of analysis. Any differences in positive rates were mitigated by the contribution of repeat testing to the identification of newly infected patients. Given these findings, and the difficulty of tracking repeat testing over time, visit-level analysis are appropriate for comparing programme outcomes when detailed modeling of epidemiology, cost, and/or outcomes is not required.