SHARP Takes on HIV Prevention: Meta-Analytic Efficacy Evidence. Blair T. Johnson. University of Connecticut Storrs, Connecticut, USA

Transcription

1 SHARP Takes on HIV Prevention: Meta-Analytic Efficacy Evidence Blair T. Johnson University of Connecticut Storrs, Connecticut, USA

2 SHARP Takes on HIV Prevention: Meta-Analytic Efficacy Evidence in (a) Africa and (b) for African-Americans Blair T. Johnson University of Connecticut Storrs, Connecticut, USA

3 HIV Prevention This Talk Some Basics about HIV/AIDS How best to prevent HIV? A little evidence My meta-analysis team, SHARP Factors Underlying Successful HIV Prevention for: African-Americans (U.S.) African countries Conclusions and Future Directions 3

4 The Problem of AIDS 4

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6 HIV/AIDS in Global Perspective AIDS remains a huge global problem New cases continue to accrue at alarming rates No short-term term hope for a cure or a vaccine Anti-retroviral medications (HAART) help symptoms (with caveats) BEHAVIOR CHANGE remains the best hope for slowing the pandemic. 6

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8 Problem: How Best to Prevent the Spread of HIV? (CUMULATIVE References to HIV or AIDS Prevention; 4 Major Databases) Knowledge Explosion or Evidence Monster? PsycINFO Scopus PubMed 8 Cumulative published references 0 2,500 5,000 7,500 10,000 12, Year

9 S.H.A.R.P. Syntheses of HIV/ IV/AIDS IDS Research Project in the Center for Health, Intervention, and Prevention (CHIP) at the University of Connecticut (Storrs, CT, USA). Supported by the U.S. National Institutes of Health from 1998 to 2007 (R01-MH58563) Published numerous meta-analyses analyses (syntheses) of HIV-related empirical literature. 9

10 The SHARP Research Team Past and present 10

11 The SHARP Research Team Past and present Blair T. Johnson, PI Michael P. Carey, co-i Leslie B. Snyder, co-i Kerry L. Marsh Judy Y. Tan Angela White Aaron Smith-McLallen Tania B. Huedo-Medina Lori A. J. Scott-Sheldon Natalie D. Smoak John F. Dovidio Karin Weiss Jessica LaCroix Amanda Northridge Jennifer J. Harman Marcella H. Boynton Michael Copenhaver Pamela Lavallee Allecia E. Reid I-Ching Lee Stephenie Chaudoir Sarah A. Lust Leah Donsky Jennifer Ortiz Many study authors 11

12 SHARP Goals Conduct research syntheses (meta-analyses) analyses) of empirical evidence related to Foundations of HIV/AIDS risk behavior HIV prevention interventions Health promotion efforts, generally. Each review is like an empirical history of the studies results. 12

13 SHARP Goals By seeing trends across many similar studies trustworthy trends may be identified. We can see whether similar strategies produce similar effects: in different locales, at different times, and for different groups of people, among other things! 13

14 SHARP s Research Programs HIV / AIDS Health Promotion Sexual Behavior Drug Behavior Comparisons to Other Health Behaviors Methods General methods for meta-analysis Correlates of of Sexual Condom Risk Behavior Use Prevention of Drug-Risk Behavior Increasing Factors condom that May use (Kalichman Affect et Any al., 1996; Reduced needle sharing Behavioral Increased works Intervention cleaning Populations Theories (Johnson, of Reasoned in press; Johnson Action & Planned Boynton, Behavior in press; Johnson & Lower Eagly, SES 2000; Populations strata (Albarracín, Johnson, Scott-Sheldon, et al., 2001; Albarracín Snyder, et Noar, al., 2004) & Heudo-Medina, 2008) Adolescents Adults Reducing MODE frequencies Model, of Auto-Motive sexual acts (Smoak Model et al., 2006) Lower SES strata Drug (Johnson et al., 2006; Marsh et al., 2001, 2006; Adolescents Adults users Improving Increased Sample condom-use seeking size of drug & skills publication treatment (Johnson bias programs et al., 2003, 2006) (Johnson, Carey, (Copenhaver, & Muellerleile, Johnson 1997; et al., Johnson 2006) et al., 2006) Improving partner-interaction HIV-positives Boynton & Johnson, (Johnson skills 2006) &(Johnson LaCroix, et al., 2003) 2007) Drug Adults users Group size (Johnson et al., in prep) Enhancing motivation to prevent HIV (Johnson et al., 2006; Many HIV-positives Drug ethnicities users Scott-Sheldon Organization (Amico, & Harman, Johnson, span & 2006; (Johnson Johnson, Smoak et 2006) al., et in al., prep) 2006) Many Primarily ethnicities U.S. Biological Participant vs. self-report Gender (Johnson indices et of al., risk in prep) behavior Worldwide (Johnson, Li, & Carey, in prep.) Weinhardt et al., 1999; Johnson et al., 2003, 2006; Scott-Sheldon & Johnson, 2006) Interpreting and translating meta-analytic findings Improvement of HAART Adherence (HIV+) 14

15 HIV Prevention Efforts Studies typically target at-risk populations. Interventions often try to use behavioral theory. Interventions typically intensively stress: 1. Critical information (e.g., describing which behaviors are risky or conveying facts about HIV/AIDS) 2. Fewer emphasize skills-building (e.g., role-playing, condom skills; negotiations) 3. Fewer still emphasize motivational training (e.g., motivational interviewing). Those with all 3 match the Information-Motivation Motivation- Behavioral Skills Model (or IMB; Fisher & Fisher, 1992). 15

16 Race and HIV Incidence, U.S., 2005 New HIV/AIDS diagnoses in % % of population African-Americans Americans Whites Source: Mortality and Morbidity Weekly Report, Centers for Disease Control and Prevention, National Center for HIV/AIDS 16

17 Goals of Our Review Examine Intervention Efficacy As a function of facilitator-participant matching on race and on gender. As a function of elicitation research to generate intervention content. As a function of IMB components. As a function of social structure over time. 17

18 ANES Use items from the American National Election Surveys (ANES) to gauge: Liking of African-Americans Americans toward own race Liking of Whites toward own race Liking of African-Americans Americans towards Whites Liking of Whites toward African-Americans Americans 18

19 Inclusion Criteria Face-to to-face techniques (no mass media) Racial features of participants and facilitators known Sample consists of at least 50% African- Americans Use of a controlled design 19

20 Included Studies 230 studies initially considered 30 studies in meta-analysis, analysis, providing 49 statistically independent groups 8,235 participants in total Sample current through May, 2006 (Another near-final meta-analysis analysis reviews the entire literature of RCTs, k = 75 reports, 114 interventions.) 20

21 Database Construction Code Studies on Important Dimensions SHARP coding Variables from ANES Standardize the Outcome Measures: d = M Treatment M Control SD Pooled 21

22 Study Characteristics When conducted? (M=1995) Publication in journal 92% Conducted in large city 59% 22

23 Where Did the Trials Take Place? Northeast West North central South 23

24 Intervention Characteristics M (sd( sd) ) % Group size 9.34 (8.85) Number of sessions 4.51 (3.81) Session time (min) 132 (91.06) Total time (hours) 7.17 (5.85) Number of facilitators 1.64 (0.56) Gender similarity 54% Ethnic similarity 83% 24

25 Samples Described by the ANES Proportion African-Americans Americans in study region M (sd( sd).12 (.07) Income: African-Americans Americans -.75 (.52) Social class: African-Americans Americans (.20) 25

26 Condom-Use Effect Sizes Varied Widely Precision > p > > p > 0.01 p < 0.01 Studies Effect size (d) Increased Risk Reduced Risk 26

27 Racial Matching Effect size ( d ) Matched Partial match 27

28 Elicitation of Content (p<.01) Effect size ( d ) None Informal Systematic 28

29 Gender Matching (p<.01) Effect size ( d ) Matched None or Partial match 29

30 Gender (p<.01) Effect size (d) Proportion females in sample All female All male 30

31 IMB Effect size ( d ) Not full IMB Full IMB 31

32 Whites Attitudes toward African- Americans (p<.001) Effect size (d) Whites' Liking of African-Americans More positive 32

33 African-Americans Attitudes toward Whites (p<.05) Effect size (d) African-Americans' Liking of Whites More positive 33

34 African-Americans Group Esteem (p<.001) Effect size (d) African-Americans' Liking of Own Race More positive 34

35 Whites Group Esteem (p<.001) Effect size (d) Whites' Liking of Own Race More positive 35

36 Moderator Analysis Thermometer Data (R 2 =.572) Race and Racial Target β African-American group esteem.6464*** Whites attitudes toward African-Americans * African-Americans attitudes toward Whites ** Whites group esteem.4806*** 36

37 Relation of Thermometers to Effect Size Effect size (d) Whites re: African-Americans African-Americans re: Whites Whites group esteem African-Americans group esteem Thermometer value Relation of Thermometers to Effect Size 37

38 Conclusions Group esteem appears to matter. Prevention success for African-Americans Americans appears to depend on social structural factors. More positive group esteem promotes efficacy and more negative group esteem impairs it. Highlights the importance of the environment that intervention recipients face when they leave the intervention. 38

39 Racial Climate, Time, and Condom Use Redux Measurement intervals Short-term term Long-term Group Esteem ( 12 weeks) (13 to 104 weeks) for African-American β = 0.13 β = 0.45*** for Whites β = β = 0.60*** Mean effect size d + = 0.27*** d + = 0.08** Consistency Consistent Inconsistent 39

40 Conclusions In the end, prejudice of Whites toward African- Americans appears not to matter why? Caveat: Why is Whites group esteem so powerful for African-Americans? Americans? Alternative explanations for racial climate effects? Not region, time, religiosity, social class, or income. 40

41 Conclusions Use of structural indexes broadens the view of HIV prevention activities: We need to think about how the environment will impair or facilitate maintenance of behavior change. If intervention content may matter less than what occurs following the intervention, it could dramatically change how we think about interventions. Caveat: Results deserve careful replication and potentially extension. Caveat: Don t t forget results are preliminary! 41

42 HIV Prevention in Africa 42

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45 Goals of Our Review Examine Intervention Efficacy as a Function of: Demographic factors (gender, age) HIV prevalence Attrition Including all 3 IMB components as intervention content 45

46 Gather relevant studies Studies qualified if: Methods Trial took place in an African nation and it evaluated the efficacy of an HIV prevention effort (relative to a control group) on a behavioral outcome. Thirty-one reports provided tests of 40 trials. 46

47 Describing the Trials Completed between 1986 and 2003 Design: RCT (42%); other group comparison (58%) Participants (N( = 76,627) were: Predominately female (61%) Mostly urban (58%; another 23% had both rural and urban) Mean reported HIV prevalence was 24.3% (range: 0 to 100%) 47

48 Describing the Interventions Interventions: Were not very long (only 32% had more than 3 hours of content) Focused on either individuals (45%) or small groups (55%) Focused on increasing consistent condom use (65%) more than reducing sexual frequencies (45%) or abstinence (16%) 48

49 The Trials Outcome Measures Reported condom use (95%) with: Steady partner (20%) Casual partner (33%) Clients (5%) Condom use (general) (68%) Reported frequency of sexual encounters (55%) Reported STD or HIV incidence (18%) 49

50 Where Did the Trials Take Place? 50

51 Efficacy Varied Widely (All Outcome Measures) Weight (inverse variance) > p > > p > 0.01 p < 0.01 Studies Effect size (d) Increased Risk Reduced Risk 51

52 Average Efficacy by Outcome Reduced risk Effect size (d ) Positive effect No effect Condom use Sexual frequencies HIV/STD k = 38 k = 22 k = 7 Reversed effect. 52

53 Condom Use Efficacy Weight (inverse variance) > p > > p > 0.01 p < 0.01 Studies Condom use (d) Increased Risk Reduced Risk 53

54 Interventions Improved Condom Use More When HIV Prevalence Was High Reduced risk Effect size (d) k = 22 (55%), R 2 =.34, p < HIV Prevalence (%) 54

55 Efficacy by Age Group (Condom Use) Reduced risk Effect size (d ) Medium effect Small effect 0 Adolescents Young adults Adults Mixed k = 12 k = 8 k = 8 k = 10 55

56 Interventions Efficacy Decayed Over Time (Condom Use) Medium effect Small effect No effect Effect size (d) R 2 =.28, p < Time (in days) after intervention 56

57 Gender at Baseline and Efficacy at 1 st Follow-Up (Condom Use) Medium effect Small effect No effect Effect size (d) R 2 =.02, p = Percentage female at baseline 57

58 Gender at Follow-Up and Efficacy (Condom Use) Medium effect Small effect No effect Effect size (d) R 2 =.15, p < Proportion females in sample at first follow-up 58

59 Change in Gender Composition between Baseline and Follow-Up Percentage (%) p <.001 Females Males 0 Pretest 1st Follow-Up 59

60 Gender and Efficacy over Time (Condom Use) Medium effect Small effect No effect Effect size (d) Males R 2 =.40, p <.001. Females Time (in days) after intervention 60

61 IMB Effect size ( d ) Not full IMB Full IMB 61

62 Conclusions Interventions in Africa have succeeded in increasing condom use, but more rarely succeed with sexual frequency outcomes or with HIV and other sexually transmitted infections. 62

63 HIV Prevention, Effects on Sexual Frequency (k = 174 studies, N = 116,735 participants) Sexual Activity Status Number of Occasions Numbe r of Partne rs 0.2 Effect size ( d) All 3 IMB Components Present Smoak, Scott-Sheldon, Johnson, & Carey, 2006, JAIDS, 41,

64 Conclusions Efficacy depended on gender and age: Younger samples, especially young adults changed more. Interventions that mixed ages did worse tailoring appears important. Decay and gender issues: Effects appear stable over time for males. Apparent decay (and attrition) for women. A greater focus on the system surrounding gender is indicated (power, norms, poverty). 64

65 Conclusions Some evidence to support IMB, but evidence is thin, with only 4 studies that satisfied IMB criteria. The intense need for any kind of prevention in Sub-Saharan Saharan Africa may help make any sort of prevention effort work. 65

66 Conclusions Prevention works better for samples exhibiting (or in locales with) high prevalence of HIV. Prevention works for individuals who are (presumably) HIV-negative, but especially for those who are HIV-positive. How do effects compare to other health behavior change efforts? 66

67 Interventions Mean Effects Compared to Cohen s Standards Mean effect size ( d ) Health Promotion Large Medium Small HIV Prevention Meta-analysis 67

68 General Conclusions Although typically not huge effects, HIV prevention efficacy is usually much larger when: Skills are improved. Motivation to act safe is enhanced. Structural impediments are removed (resources are enhanced). These elements are robustly associated with reductions of HIV-risk behavior and align with the IMB Model (Fisher & Fisher, 1992). 68

69 General Conclusions The 3 IMB elements do not always combine to create greatest efficacy. Why? Different groups have differing needs. E.g.s: U.S. Adolescents need skills (Johnson et al., 2003) Africans may need all elements (note age effects) Different behaviors may be driven by different factors. E.g.: Condom use (or unprotected intercourse) tends to be a higher- frequency behavior than altering number of partners. Decreasing numbers of sexual partners may be driven by factors that t interventions do not regularly target. Highlights role of doing elicitation research to determine largest risk deficits and to tailor messages accordingly (Fisher & Fisher, 1992). 69

70 General Conclusions Best Routes to Effective HIV Prevention Consider All High Quality Studies Rather than A Few Isolated Studies Good HIV Prevention Strategies Should: reliably decrease behaviors that may spread HIV, do so with great efficacy, work with different groups, and have lasting effects Meta-Analysis Is an Important Tool to Demonstrate these Trends and to Tame the Evidence Monster! Yet It Is Not a Panacea. 70

71 Limitations It takes time for HIV prevention studies to appear in research syntheses. What is learned here is a historical record and somewhat dated. Active involvement with communities the the local social culture is an important component to effective prevention we need to transition from efficacy to effectiveness. 71

72 Other Future Directions How Can We Be SHARPer? SHARP is currently focusing on prevention in: Latin America Asia Biological outcomes of HIV prevention success Past behavior as a moderator of prevention success, including behavior change maintenance Mass media interventions And more!... Including a Competing Renewal Proposal 72

73 Thank you for your attention! 73

74 Racial Climate and No. of Partners (Prevention for African-Americans) Effect size (d) African-Americans regarding Whites Whites Group Esteem k = 16, R 2 = , p <.001. Whites regarding African-Americans Racial thermometer mean African-American Group Esteem Relation of Thermometers to Effect Size 74

75 Condom-Use Efficacy and Sample Age (Prevention in Africa) 0.5 R 2 =.32, p < Effect size ( d ) Adolescents Young adults Adults Mixed k = 13 k = 8 k = 8 k = 11 75

76 Partner in Condom-Use Measure (Prevention in Africa) Effect size ( d ) Steady partner Casual partner Clients Unspecified k = 7 k = 10 k = 2 k = 27 76

77 What is the Best Evidence: A Single Study or Trends across Similar Studies? The CDC s s DEBI project (Diffusion( of Effective Behavioral Interventions) has highlighted 18 interventions as models for use in U.S. communities. (See Yet it is currently unclear how well these studies reduced risk relative to non-debi studies. 77

78 One View on the Evidence Monster In fact, as the CDC acknowledges, there are hundreds of potentially relevant interventions available. Source: CDC,