Use of conjoint analysis to

assess HIV vaccine acceptability

in three populations:

An innovation in the assessment of consumer healthcare preferences

(Project VIBE)

Sung-Jae Lee, Ph.D., Peter A. Newman, Ph.D., William E. Cunningham, MD, M.P.H.,

Danielle Seiden, M.P.P., Naihua Duan, Ph.D.

• Background Assessing HIV Vaccine Acceptability

• Methodology Conjoint Analysis

• Results Three Samples

• Conclusions Application in HIV Vaccine Acceptability

Outline

BACKGROUND

What will happen when HIV vaccines become

publicly available?

“If we build it, they will come!”

…but will they???

Sub-optimal Uptake of Existing Vaccines

• Non-institutionalized U.S. adults 18 – 64 yrs 23% – 47% influenza vaccine 20% – 58% pneumococcal vaccine Lower coverage rates – African

Americans, Latinos, low SES

HIV vaccine uptake is not guaranteed

Conjoint Analysis

• Well established research technique to

predict consumer preferences when faced

with a number of products varying across

specific attributes (Green, 1999)

• Extensive use in psychology, marketing,

and economics

Conjoint Analysis

• Growing application in measuring health

care preferences (Phillips 2002, 2006),

ranging from microbicide use (Holt, 2006)

and anti-inflammatory drugs (Fraenkel,

2004) to hearing aids (Meister, 2002)

and glaucoma treatment (Bhargava, 2006)

Objective

• Conjoint Analysis

To test the feasibility of conjoint analysis application to measure HIV vaccine acceptability among three diverse communities in Los Angeles, California and Toronto, Canada.

METHODS

Participants

• Multi-ethnic communities in Los Angeles, California At risk communities; Individual interviews;

n=143

• Thai Residents in Los Angeles, California Three focus groups; n=27

• Aboriginal Canadians, Toronto, Canada Two focus groups; n=13

• Assigning levels of attributes:

Integrating input from focus group results, HIV vaccine experts, published and unpublished literature

Hypothetical HIV vaccine being composed of a bundle of 7 dichotomous attributes

Conjoint Analysis Methods

HIV Vaccine Attributes

• Assigning conjoint scenarios:

(27= 128) hypothetical scenarios

Fractional factorial design

8 hypothetical HIV vaccines

• Conjoint analysis in different modalities

Conjoint Analysis Methods

Rating Hypothetical HIV Vaccines

Rate eight hypothetical HIV vaccinesfrom “Highly likely” to “Highly unlikely”

Conjoint Scenario Cards

• Estimate acceptability score for each vaccine by averaging individual vaccine ratings across participants

• One sample t-test to determine impact significance

Conjoint Analysis Methods

RESULTS

HIV Vaccine Acceptability

HIV Vaccine Acceptability

Multi-ethnicLos Angeles

sample (n=143)

Los AngelesThai communitysample (n=27)

Aboriginal Canadian

sample (n=13)

Acceptability rangeacross eight

vaccines (100-point scale)

33.2 to 82.2 7.4 to 85.2 28.8 to 84.6

HIV Vaccine Acceptability

Impact of Vaccine Attributes on HIV Vaccine Acceptability

CONCLUSIONS

• Conjoint analysis provided insight into HIV

vaccine acceptability among diverse potential consumers

Vaccine acceptability varied widely across 8 vaccines with different attributes

Efficacy had the greatest impact on acceptability

Attribute impacts varied across three samples

Conclusions

• We demonstrated successful applications

of conjoint analysis

Individual setting ( with a skilled interviewer)

Group setting (with trained facilitators)

Conclusions

Marketing & Economics

Biomedical Science

BehavioralScience

Conjoint Analysis

HIV Vaccine Acceptability

New Initiatives• L.A. VOICES: Post-trial HIV Vaccines:

Receptivity, Risk & Disparities (R01-MH-069087-01A1)

• Sisters, Mothers, Daughters & Aunties: Protecting Black Women against HIV (Canadian Institutes of Health Research)

• HIV Vaccine Acceptability in Thailand (Social Sciences & Humanities Research Council, Canada)

• HIV Vaccine Trial Participation & Community Engagement (Ontario HIV Treatment Network)

VOICESL.A.

VOICESVOICES

• Duan N. Listening to consumers and HIV vaccine preparedness. Lancet. 2005 Apr;365(9465):1119-21. [See also The Lancet: The trials of tenofovir trials. Lancet. 2005 April;365(9465):1111.)]

• Newman P.A., Duan, N., Lee, S-J., Rudy, E.T., Seiden, D.S., Kakinami, L., Cunningham, W.E. HIV vaccine acceptability among communities at risk: The impact of vaccine characteristics. Vaccine. 2006 Mar 15;24(12):2094-101.

References

• UCLA AIDS Institute Seed Grant (CC99-LA-002)

• UCLA AIDS Institute and Palotta Teamworks AIDS Vaccine Rides

• Center for HIV Identification Prevention and Treatment Services (P30 MH 58107)

• Social Sciences and Humanities Research Council Institutional Grant (Canada)

Supported By

Acknowledgements

• Thanks to Peter Anton, Lauren Arguelles, Phil Batterham, Ned Bayrd, Omar Banos, Ron Brooks, Coleen Cantwell, Suzi Cantwell, Mark Etzel, Kathie Ferbas, Neil Gajasan, Sonia Johnson, Ella Kelly, Faith Landsman, Kathy Mattes, Irma Ocegueda, Rowell Ramos, Fen Rhodes, Mary Jane Rotheram, Rassamee Sangthong, Dallas Swendeman, Julian Wang, Michael Woodford, Shin-Yi Wu, Paul Xue

• Special thanks to all participants, study sites & key informants without whom this research would not have been possible.

For more information, please contact:Sung-Jae Lee, Ph.D.Semel Institute Neuroscience and Human Behavior, UCLACenter for Community Healthsjlee@mednet.ucla.edu

Naihua Duan, Ph.D.Semel Institute Neuroscience and Human Behavior, UCLAHealth Service Research Centernaihua@mednet.ucla.edu

Peter Newman, Ph.D.University of Toronto Faculty of Social Work 246 Bloor Street West Toronto, Ontario M5S 1A1 CANADAp.newman@utoronto.ca