1. Diversity in Team Composition and Performance and Creativity
Jill A. Marsteller, PhD MPP
Assistant Professor,
Johns Hopkins Bloomberg School of Public Health
2007 Health Workforce Interest Group Meeting, Orlando, FL Saturday, June 2, 2007

2. Background Interdisciplinary teams are used often in healthcare
Team members vary in occupation, training, experience, and demographic background
“Too many cooks in the kitchen” vs. “Two heads are better than one”

3. Definitions Diversity—two types:
Visible: age, gender, (race/ ethnicity)
Invisible: occupation, tenure, education
Chronic care QI team--three or more nurses, PCPs, specialists, administrators, etc. who work to improve management of asthma, diabetes, depression, or congestive heart failure

4. Performance Vs. Creativity
Performance—reaching a set target
Creativity—production of new ideas, testing and modifying procedures
Because they’re different,

5. How diversity works
Diversity-->Social Categorization, Identification, Impersonal Attraction-->Bias, Negative Conflict, Low Cohesion-->Negative Outcomes
Diversity-->Airing Multiple Perspectives--> Positive Conflict-->Improved Decision-making-->Positive Outcomes
Literature--Jury is out on diversity

6. Research Questions
Does occupational diversity have different associations with performance as compared to creativity?
Are there mediators of the effects of occupational diversity?

7. Fig. 1--Proposed Conceptual Model for the Relation of Nonracial Diversity to Performance
(unmeasured process)
(-)
Diversity
-Visible diversity
-Invisible diversity
-Interaction variables
Team Performance
(+)
(-)
Social categorization, identification, group attraction; conflict; coordination problems
Unifying Phenomena
(Mediator)
-Goal attainment
-Patient outcomes
-Met expectations
Based on Milliken, Bartel and Kurtzberg (2001), Tsui and Gutek (1999) and Jackson, May and Whitney (1995)

8. Fig. 2--Proposed Conceptual Model for the Relation of Nonracial Diversity to Creativity and Productivity
(unmeasured process)
(-)
Diversity
Team Productivity and Creativity
-Visible diversity
-Invisible diversity
-Interaction variables
Phenomena Stressing the Individual
(+)
Social categorization, identification, group attraction; conflict; coordination problems
(-)
-Number of actions taken
-Novelty of actions
(Mediator)
Based on Milliken, Bartel and Kurtzberg (2001), Tsui and Gutek (1999) and Jackson, May and Whitney (1995)

9. Study Design and Population
Secondary data analysis
OLS and Logistic regression analysis
~40 teams from hospitals, physician groups, clinics, health plans, or health systems participating in 3 Improving Chronic Illness Care Collaboratives (evaluation-ICICE)
Surveyed members of multi-disciplinary teams
Size 1 to 14 members
As many as 12 occupational categories

10. Data Level of analysis--the team
Some measures constructed for the team from individual-level data
means
CVs (Allison 1978)
Heterogeneity index, H= 1-S pi2 (Blau 1977)
Some measures collected at team level

11. Variables

12. Analytic Methods
Mediated regression analysis using repeated OLS (Baron and Kenny 1986)
Examines, in additive steps:
controls
main effects of variables of interest
moderating effects
mediators (to see if relationships change)
Conditions for pure mediation:
Independent variables affect the mediator
Independent variables affect the DV
Mediator affects the DV when included with independents, effect of independent variables is reduced
An exploratory analysis

13. Results--Simple Statistics
A 25/25/25/25 split would be 100% diversity. This shows more diversity in occupation than in gender or educational levels, but less than age diversity. Job tenure is a different measure (CV).

14. Results--T1 Self-Assessed Team Performance
On a performance measure, Occupational diversity slightly increases team self-assessment at the beginning of the collaborative controlling for other types of diversity, mean team experience and size, organizational type, and collaborative. Model explains more than half the variance in team self-assessment.

15. Results--Number of Changes in Care Practices
This is a creativity outcome, number of changes made to care during the collaborative. Occupational diversity does not have significant effects (none of the diversity measures did). However the measures of team process, participative norms on the team and autonomy, both increased the number of changes made. Lack of diversity effects may be in part due to controlling for first period self-assessment. Teams that self assessed higher at the beginning of the collaborative did not make as many changes to improve care.

16. Results--Innovativeness
Another creativity measure—innovativeness. This is defined within the sample, meaning rare changes as a percent of all changes, not some outside standard of creativity. Again, no effects of occupational diversity.
Autonomy and participation again increase innovativeness.
Of interest is that larger team size is better to a point, and then brings diminishing returns. This was true for number of changes made as well.

17. Results--T2 Self-Assessed Team Performance
Another performance measure, self-assessed performance as rated at the end of the collaborative. Remember Occupational diversity was beneficial to early self-assessment. At the end of the collaborative, it has no effect on performance, controlling for time 1 self-assessment and the number of changes made to improve care. There is a positive effect of team self-assessed skill that may make up for a slight negative effect of age diversity on the team.

18. What have we learned?
Occupational diversity had a positive effect on T1 self-assessed performance
But no effect on T2 self-assessment
And no effect on the 2 creative outcomes
So it’s good for starters and makes no difference after a while, when the positive start-up effect is accounted for

19. Limitations
Small N means that sophisticated analysis of all effects is impossible. Models are stretched to their limits.
Multicollinearity likely mutes some potentially significant effects of diversity measures.

20. Conclusions
Diversity can be one possible barrier to team quality improvement
But sometimes is a boon
Insight into how to maximize benefits of teamwork
Keep teams together longer (change in diversity’s effects over time)
Seek to manage negative effects of diversity with cohesion-building efforts
Encourage individual participation and grant autonomy