Social Cohesion: Notes & Sources

Social Cohesion: Notes & Sources


Confidence interval (also called "error bar") is therange of values that includes the true value 95% of the time. If the confidence intervals of two groups do not overlap, the difference between groups is statistically significant (meaning that chance or random variation is unlikely to explain the difference).   

King County regions: The geographic boundaries of the four King County sub-regions (North, Seattle, East, and South) are defined by the aggregation of ZIP codes. See map of regions here.

Race/Ethnicity: Federal standards mandate that race and ethnicity (Hispanic origin) are distinct concepts requiring 2 separate questions when collecting data from an individual. "Hispanic origin" is meant to capture the heritage, nationality group, lineage, or country of birth of an individual (or his/her parents) before arriving in the United States. Persons of Hispanic ethnicity can be of any race. Communities Count's terms for racial/ethnic groups are derived from those used by the U.S Census Bureau in 2010.

  • Communities Count terms:  Hispanic, Non-Hispanic, White Non-Hispanic, Black, American Indian/Alaska Native (AIAN), Asian, Native Hawaiian/Pacific Islander (NHPI), White, and Multiple Race (Multiple). Persons of Hispanic ethnicity can be of any race and are included in other racial categories. Racial/ethnic groups are sometimes combined when sample sizes are too small for valid statistical comparisons of more discrete groups. 
  • 2010 Census terms: Hispanic or Latino, Not Hispanic or Latino, White alone (Not Hispanic or Latino),  Black or African American, American Indian or Alaska Native, Asian, Native Hawaiian or Other Pacific Islander, White, Some Other Race, and Two or More Races.
  • NOTE: The numbers of American Indian/Alaska Native and Pacific Islander respondents were too small to permit calculation of reliable scores for these groups, so responses from these groups were combined in the category, ‘other races.’

Social cohesion (also referred to as “collective efficacy”) is generally understood as mutual trust among neighbors combined with a willingness to intervene on behalf of the common good.  Neighborhoods with high levels of social cohesion tend to have lower rates of violence.


Social cohesion responses by region: The table below displays the social cohesion and informal social control questions that were combined to give the social cohesion score for a respondent’s neighborhood.  Item-level responses from those living in the East Region are consistently higher than those of respondents in other parts of the county.

Percent of adults who report high social cohesion (trust and informal social control) 
in their neighborhoods, King County (2011

Trends were mixed, depending on sampling methods. Prior to 2011,Communities Count conducted its survey exclusively via random-digit-dial landline phone contact. Starting in 2011, Communities Count broadened its sampling method to include address-based sampling for mailed questionnaires, and added an internet response option.  The new method produced a more representative sample of the county population.

  • Comparing the responses of adults interviewed in the same manner in 2004, 2007, and 2011 (landline random-digit-dial phone survey), no significant trends were revealed. 
  • However, when the 2004 and 2007 landline-only responses were compared to all responses of the 2011 participants (who could respond via mail or internet in addition to landline phone interviews), social cohesion appeared to decline between 2007 and 2011.
  • Although the 2011 sample was more representative of the King County population than a landline-only sample, the only thing we can with confidence is that social cohesion did not show an increasing trend.

Statistical significance: Unless otherwise noted, any difference mentioned in the text is statistically significant (unlikely to have occurred by chance).

Data Sources

Communities Count Survey (2004, 2007, 2011):  Respondents came from a random sample of all King County households.  Due to the limitations of surveys that rely exclusively on landline telephones, Communities Count used a mixed-mode survey involving both random-digit-dial phone contact and address-based sampling for mailed questionnaires, with an internet response option as well. Phone interviews were conducted in English, Spanish, and, upon request, a few additional languages. Possible limitations of this kind of survey include: (a) people who do not have a telephone or a permanent address are missed; (b) people who do not speak English or Spanish may not participate; (c) people who have less education and lower incomes tend to be under-represented.

Neighborhood social cohesion scores were derived from questions on trust and informal social control reported in the study "Neighborhoods and Violent Crime: A Multilevel Study of Collective Efficacy" by Robert J Sampson, Stephen W. Raudenbush, and Felton Earls. Science 277 (1997): 918-24.

Other Sources

Maps of King County covering a wide range of topics can be accessed at  Maps most immediately relevant to Communities Count are under the headings of Community data & demographics, Public health, and Environment & natural resources, but other maps should be useful as well (farmers markets, transit routes, walking and biking routes, parks, traffic counts, etc.).

Quotes:  Communities Count interviewed 32 King County parents or guardians raising at least one child younger than 6 years of age.  We reached out to communities of color, recent immigrants, and residents with limited English proficiency to achieve a broad range of racial, cultural, and socioeconomic diversity. We interviewed both families with very low household income and those who earned up to median income (about $68,000 for a family of four in 2010). Family structures included single-parent households, couples living in consensual unions, married couples, and extended families.

Report of High-Level Task Force on Social Cohesion. Towards an active, fair and socially cohesive Europe. Strasbourg, 28 January 2008.

Social cohesion and violence is discussed in an article by I. Kawachi and B.P. Kennedy, Health and social cohesion: why care about income inequality? BMJ 1997 April 5; 314(7086): 1037-1040.