1. Measures of Acculturation Nazleen Bharmal, MD, PhD RCMAR/CHIME and Project EXPORT Methods Seminar August 2013

2. Acculturation Process by which individuals exposed regularly to another culture adopt the attitudes, values, customs, beliefs, and behaviors of the foreign culture Unidirectional vs. Bidirectional Health Outcomes: depression, obesity, DM, CVD, cancer Health impact depends on how acculturation is measured

3. Measures of Acculturation Acculturation Scales: –Cultural practices, values, identification –Hispanics: ARSMA, SASH, BAS –Asians: SL-ASIA Proxy Measures: –Language proficiency –Country of nativity –Temporal: length of residence, age at immigration

4. California Asian Indian Tobacco Survey Telephone survey of 3228 Asian Indian adults RR=81% (adult), 54% (house x adult) Conducted in several South Asian languages

5. Acculturation Domains DomainQuestion & Responses Language use 1. English as primary language? Y/N 2. How often native language spoken at home? Likert scale 3. Language of the interview? English, Gujarati, Hindi, Punjabi Media behavior 1. How often do you read Indian newspapers, magazines, books, or content on the internet? Likert scale Social customs 1. How often do you eat Indian food? Likert scale 2. How open would you be to your son/daughter marrying outside of cultural group? Likert scale 3. Do you observe traditional holidays impt in your culture? Likert Social contacts 1. How often keep in contact with family and friends in India? Likert Ethnic identity 1. Self-reported ethnic identity measured on a 5-response scale: Full Indian, Indian first-American second, Equal blend, American first-Indian second, Full American Generational status 1. Generational status? 1 st or 2 nd + generation 2. Born in a developed country? Y/N

6. Temporal Measures Duration of residence in the U.S. Percentage of time in the U.S. Age at immigration

7. Relationship Between Ethnic Identity and Number of Years in the U.S. Acculturation Items% sampleMean yrs95% CI Full Indian247.6(7.1, 8.1) Indian 1 st, American 2 nd 1612.3(11.3, 13.2) Equal Indian, American5014.4(13.8, 15.0) American 1 st, Indian 2 nd 617.1(15.0, 19.2) Full American618.7(16.3, 21.2) F-test p-value<0.001; r = 0.32

8. Associations of acculturation items and number of years in the US

9. Evaluation of Dimensionality of Acculturation Items

10. Exploratory Factor Analysis: criteria for determining number of factors –PCA eigenvalues > 1 –Scree test plot: graphical display of components and corresponding eigenvalues –Parallel analysis: based on a Monte Carol simulation, compares observed eigenvalues with uncorrelated normal variables

11. EFA Examples

12. Factor Rotation Rotate plausible number of factors –Look for simple structure –Orthogonal v. Oblique (permits factor correlation) STATA Command: estat common estat structure rotate, promax factors (#) griegan, yline (1) estat smc

13. Factor 1Factor 2 Frequency of contact with family & friends in India0.7880-0.2501 Frequency read Indian media0.6329-0.0152 Generational status/Born in developed country0.5939-0.0114 Frequency native language spoken at home0.52780.3916 Frequency eat Indian food0.50160.2014 Self-assessed cultural identity0.48210.0725 Language of interview-0.15030.7570 How open to child marrying outside cultural group-0.07030.7177 English as primary language0.24640.5688 Observe traditional holidays in your culture0.09580.5216 Promax obliquely rotated 2-factor solution Factor 1 – Engagement in Indian cultural behaviors; Factor 2 – Social behaviors in US Bold – factor loading > 0.40

14. Confirmatory Factor Analysis Specify specific model and evaluate fit Model fit evaluation: –Chi-squared tests –Goodness of fit index –RMSEA (root mean square error of approximation) –CFI (comparative fit index – relative to null)

15. Parameter estimates for CFA model ITEMNullFactor 1Factor 2 Factor 1: Indian cultural behaviors Frequency native language spoken at home0.711.00- Frequency eat Indian food0.450.60- Frequency read Indian media0.430.57- Generational status/Nativity0.390.52- Self-assessed cultural identity0.350.50- Frequency contact w/ family & friends in India0.380.49- Factor 2: Social behaviors in U.S. English as primary language0.53-1.00 How open to child marrying outside group0.36-0.72 Observe the traditional holidays in culture0.37-0.72 Language of interview0.34-0.55 Factor 1Factor 2 Factor 11.00 Factor 20.081.00

16. Confirmatory Factor Analysis 1-Factor Model: –RMSEA (0-1) = 0.10 –CFI (0-1) = 0.65 2-Factor Model: –RMSEA = 0.08 –CFI = 0.79 2-Factor Model with correlated residuals: –RMSEA = 0.07 –CFI = 0.89 RMSEA: Smaller values indicate better model fit ≤ 0.06 CFI: Larger values indicate better model fit ≥ 0.90

17. Scoring of Acculturation scale Transformed each of items to have a 0- 100 possible range –e.g., frequency of native language had 5 response categories (1-5) that became: 0, 25, 50, 75, 100 Higher score means greater level of acculturation to U.S.

18. Acculturation Scale Characteristics 11-items averaged together Mean = 39 (range: 0-100; SD 17) Skewness = 0.45, Kurtosis = 3.05 Internal consistency reliability = 0.73 Product-moment correlations with: – r = 0.37 with years lived in the US – r =0.45 with percentage of lifetime in the US – r = -0.34 with age at immigration

19. Mean acculturation score by yrs in U.S. among immigrants

20. Acknowledgements Ron Hays – for methods mentoring William McCarthy – for content mentoring NRSA, AHA, STAR fellowships Validity of Temporal Measures as Proxies for Measuring Acculturation in Asian Indian Survey Respondents. J Immigr Minor Health. 2013