The Los Angeles County Department of Public Health serves nearly 10 million diverse residents across urban, suburban, and rural areas. To assess community needs, and to plan, evaluate, and inform public health programs and policies for this unique region, the Los Angeles County Department of Public Health (DPH) has since 1997 conducted the Los Angeles County Health Survey (LACHS). This population based telephone survey, conducted through DPH's Office of Health Assessment and Epidemiology, functions as the County’s primary vehicle for gathering information about access to care, health services utilization, health behaviors, health status, and knowledge and perceptions of health-related issues among the LA County population.
The large sample size of the LACHS enables the survey to provide population estimates of the health of the County population, along with sub-County populations including a large variety of geographic, racial/ethnic, and socioeconomic groups. Statistical weighting is utilized to generalize the sample survey data to the overall LA County population. Data are collected from households of all educational and income levels, including low income populations and the most vulnerable residents living below the federal poverty level. Importantly, the survey allows the Department of Public Health to track health issues over time. To properly address the root causes of poor health, the survey looks beyond risk factors for individuals diseases to factors in the physical and social environment that influence health, such as land use, safety, poverty, and educational attainment. The LACHS has been conducted in 1997, 1999, 2002, 2005, and 2007, and data have been collected for 2011. Each LACHS has included an adult component and a child component, administered to the parent or guardian of a child 0-17 years old. Recent surveys have also included 7 or 8 subsample sections, each administered to a portion of the adult survey population. In 2007, a total of 7,200 adults (ages 18 years or older) residing in LA County were interviewed for the Adult survey. In addition, 5,728 interviews were conducted among the parents (primarily mothers) of children ages 17 years or under. Respondents in each household were randomly selected using an unrestricted digit dial sampling methodology, which included all eligible LA County households with landline telephones. Interviews were conducted in English, Spanish, Chinese (Mandarin and Cantonese), Korean and Vietnamese. Governmental organizations (local, county and state), community-based organizations, researchers, policy makers (advocacy groups) are among the many users of the LACHS data. The data may be used for LA County Department of Health Services Evaluation and Program Planning, Community Health Assessment, public education and funding proposals/grant applications. Results are disseminated through health briefs, fact sheets, comprehensive reports, presentations, press releases/conferences and on the web. The LA County Department of Public Health Office of Health Assessment and Epidemiology (OHAE) provides data through data requests and reports as well.
Assessment is a core function of all public health agencies, as localities must be able to monitor population health status to identify and mitigate community problems. Assessment drives evidence-based public health practice by informing and supporting the other core public health functions, policy development and assurance. However, challenges arise in finding timely, population-based data to meet the assessment needs of a local public health department. Relevant information is most useful when it is available at the community level, but local health jurisdictions typically lack the resources to collect and analyze the broad range of data necessary for comprehensive assessment. Since 1997, the Los Angeles County Department of Public Health (DPH) has been fortunate to be able to perform its own periodic health survey, in order to have local data available for program planning, evaluation, and policy development. The purpose of the health survey is to provide updates on key health indicators and to identify emerging public health issues among adults and children residing in the County's eight service planning areas (SPAs) and 26 health districts. The LACHS identifies disparities across populations, including subgroups based on gender, age, race/ethnicity, income, education, and geography; tracks health trends over time; allows compare the health of LA County residents with state and national data; and to benchmark them against national health objectives such as Healthy People. Over the years the LACHS has become the foundation for evidence-based public health practice by DPH programs, generating needs assessment data to shape programs and policy, and allowing for the development of population health indicators that serve as performance measures.
In 1997, the Director of the LAC DPH (then part of the Department of Health Services) commissioned an independent review of the County’s public health programs and services. This influential report, known as the Breslow Report, concluded that that there was no active assessment of the needs of diverse LA County communities which could be used to define policies and goals, or to plan and execute programs to meet those goals. The report recommended creating a centralized assessment unit to monitor the health status of the entire LA County population, including chronic and communicable diseases, environmental health, plus violence and injury prevention. As a result of this report, the Los Angeles County Health Survey and the Office of Health Assessment and Epidemiology (OHAE), charged with overseeing and running the survey, were created. For each survey cycle, OHAE develops questionnaires with input from numerous stakeholders, including DPH programs, County and academic health experts, and leaders of community-based organizations. Other large health surveys such as BRFSS, NHANES, NHIS, and the American Community Survey are consulted to model validated questions. As other localized health surveys have arisen during the past decade, such as the California Health Interview Survey and the New York City Community Health Survey, OHAE has also reviewed their questionnaires for survey items. Many public health programs provide input for the survey and contribute to the questionnaire design, including Emergency Preparedness and Response Program, Maternal Child Adolescent Health Program, Office of AIDS Programs and Policy, Tobacco Control and Prevention Program, PLACE Program (Policies for Livable, Active Communities and Environments), Physical Activity Program, Nutrition Program, Office of Senior Health, Veterinary Health, Acute Communicable Disease Control, Toxics Epidemiology, and Environmental Health. OHAE also partners with other Los Angeles County Departments including the LA County Office of Child Care, the LA County Arts Commission, and the LA County Department of Mental Health to ensure that a broad range of health-related topics are represented by the survey. Other partners that are involved in survey planning include First 5 LA, the Greater Los Angeles Breastfeeding Task Force, and academic collaborators at UCLA and USC.
The Los Angeles County Health Survey (LACHS) measures a large and important array of health indicators, such as affordability and access to health care, prevalence of chronic conditions (e.g., heart disease, diabetes, depression, hypertension), health behaviors (e.g., fruit/vegetable consumption, alcohol use, smoking status, contraceptive use), and key social measures such as neighborhood safety and parents’ difficulty in accessing child care. To properly address the root causes of poor health, the survey looks beyond risk factors for individual diseases to factors in the physical and social environment that influence health, such as land use, safety, poverty, and educational attainment. The LACHS is a random digit dial telephone survey with two main components: an adult health survey of people ages 18 and older, and a child health survey of parents of children 17 years and younger. The LACHS also includes 7 or 8 sub-samples, each administered to approximately 1,000 of the adult respondents, allowing the survey to collect additional data on a wide variety of policy related topics. Each LACHS has been conducted in a minimum of six languages, including English, Spanish, Mandarin, Cantonese, Korean, and Vietnamese. In the 2007 LACHS, 26% of all adult interviews and 43% of all parent interviews were completed in languages other than English, reflecting the diversity of our County population. Statistical weighting is utilized to generalize the sample survey data to the overall LA County population. For adult, child, and subsample data files, appropriate weights are developed to account for differences in the probability of selection of households into each sample and to align the survey results to known geographic and demographic characteristics of the County’s adult and child populations. This process involves calculating a household weight and a population rate for each individual record, and projecting the data files to the population of residential housing units and the population of non-institutionalized adults and children in Los Angeles County.
The LACHS creatively draws upon existing tools by drawing from and staying abreast of other large scale RDD telephone based health surveys conducted in the US, such as those conducted by the National Center for Health Statistics (NCHS) and the Centers for Disease Control (CDC). By recognizing and understanding methodological challenges such as declining response rates, non-coverage bias, and increasing cell phone use, and by keeping abreast of changes that the BRFSS and other large RDD health surveys have undertaken to address these issues, OHAE is able to make informed decisions and adapt our survey design and methods to a changing landscape. Over the years, the LACHS has evolved in order to maintain high quality methods and data, for example by geocoding respondents so that more precise geospatial analyses may be performed; sending pre-approach letters to increase response rates; and incorporating cellular telephones into our sample to address the non-response bias introduced by the exponential growth of wireless-only telephone households.
Declining response rates, coverage bias with random digit dialed samples, and the increasing costs incurred with cell phone samples pose major challenges to telephone-based population health surveys, including the Los Angeles County Health Survey (LACHS). In planning for the next survey cycle, OHAE and First 5 LA hosted a research colloquium on Monday, October 3, 2011 entitled, “Population-based Health Surveys: Future Design and Coverage Strategies.” The purpose of the colloquium was to convene a group of leading experts to explore practical alternative sampling frames, mixed-method survey design, and novel approaches to population survey research to inform the design of the future of the LACHS. The colloquium panelists explored alternative sampling approaches to RDD (random digit dialing) such as address-based sampling, administrative lists, web panels and respondent driven sampling. OHAE will consider these approaches and see if they can improve response rates and lower survey costs when implementing the next LACHS.
Many local health departments are unable to conduct large scale health surveys such as the LACHS. Given the County’s large, unique, diverse population, the LACHS is a valuable primary data collection tool that allows examination of valid, reliable and representative data at the SPA and health district-level. OHAE staff also conduct customized data analyses for cities and communities by combining data collected at the zip-code and census tract level. Following the 2007 LACHS, OHAE epidemiologists developed a model-based small area estimation method to create estimates for cigarette smoking and obesity for each of the County's 88 cities and over 40 unincorporated communities. These analyses, which reveal higher cigarette smoking and obesity prevalence in low-income cities, add another layer of data to our knowledge of the health inequities experienced by low-income urban communities and provide much sought data for local tobacco and obesity control. Data results for each year and reports can be accessed at OHAE website: www.lapublichealth.org/ha.
health care providers
health advocates throughout the County.
Role of Stakeholders/Partners
A broad range of partners within the Department of Public Health, the County of Los Angeles, and from throughout our community have been involved in the LACHS. Partners within and outside DPH are actively involved in questionnaire design, interpretation of data, and dissemination of results through multiple routes. Stakeholders have worked closely with OHAE during the planning stage to initially identify funding sources and to review and revise the questionnaire, addressing data gaps and identifying data needs of the community. Stakeholders and partners also work closely with OHAE to translate data findings to actionable outcomes. For example, First 5 LA, a unique child-advocacy organization, partners with OHAE to collect and make available to First 5 LA and its stakeholders population-based data on the health and well-being of children 0-5 and their families in L.A. County. First 5 LA provides partial funding for administration of the survey and analysis of the data, particularly with the goals of including survey questions relevant to the 0-5 population and oversampling in First 5 LA geographic areas of interest. The partners continue to provide expertise and guidance on survey topics; their input is critical to sustaining the survey.
The mission of the LA County Department of Public Health (DPH) is to protect health, prevent disease, and promote the health and well-being of Los Angeles County residents. As the most populous and one of the most diverse counties in the nation, improving the health of LA County residents presents an enormous, ongoing challenge. In order to address health problems, improve well-being, maximize the quality and length of life of the population, and evaluate the efforts of myriad public health programs, solid population-based data are needed. OHAE within Department of Public Health is charged with carrying out this assessment function by collecting and disseminating population-based health information to plan, evaluate, and develop local programs that serve local communities and agencies that are engaged in improving the health status of LA County residents. The main roles of OHAE have been to gather funding for the survey, design the survey questionnaire by facilitating input from all local public health sectors, implement the survey through a professional contractor, and disseminate data. The results of the LACHS are not only utilized by myriad DPH programs for planning and evaluation but are broadly disseminated throughout different sectors of the community. OHAE shares data through published reports, such as LA Health briefs and the Key Indicators of Health; through the Web site (http://publichealth.lacounty.gov/ha); through state and national conference presentations; and perhaps most importantly through fulfillment of customized data requests received from community organizations, government agencies, researchers, health care providers, and health advocates throughout the County. OHAE also collaborates with academic partners at UCLA and USC on peer reviewed journal articles and presentations at academic gatherings. LACHS data on smoking and obesity have been used to promote policy change at the local level. In short, the data collected in the LACHS and analyzed by OHAE are widely used for decision-making and program implementation to improve the health of LA County residents.
Data from the LACHS have served to mobilize community coalitions organized for the specific purpose of reducing the health risks and health disparities that afflict LA County communities and low income residents. For example, our LACHS data on health care access and health disparities within local communities have served as a critical building block in the creation of the South Los Angeles Health Equity Scorecard. The Scorecard is published by the Community Health Councils (CHC), a non-profit health promotion and education organization whose mission is to increase access to quality health care among uninsured and underserved communities. The CHC Scorecard detailed the health and physical environment inequities leading to negative health outcomes within South Los Angeles, and developed comprehensive recommendations for addressing these health disparities. By making our survey results and publications user-friendly and accessible, we facilitate use of LACHS data by diverse health advocates, including community based organizations, health professionals, academic researchers, and the media. We support many avenues for educating leaders and policy makers, and the public, about important health trends, supporting and promoting the County’s collective efforts to improve health.
In collaborating with DPH and community partners on the LACHS, we have learned valuable lessons about the process of primary data collection and dissemination. Sometimes, issues that seem of great importance to a stakeholder at the time of a survey's development are no longer relevant to public health practice or policy by the time data are collected, analyzed, and shared. For example, questionnaire items developed during a shortage of influenza vaccine, designed to reveal barriers to flu vaccination in a particular year, may no longer be of interest to the community upon their release 2 years later, during a different flu season when vaccine is in great supply. In planning the survey, OHAE must work with all of our partners to maximize the value of the LACHS, by together carefully choosing questions that will remain relevant within the length of a survey cycle. This sometimes means rejecting the ideas of collaborators, and working together to find solutions.
The LACHS is a population-based telephone survey of Los Angeles County households. It is structured to examine two separate and distinct populations within Los Angeles County.
These populations include:
Los Angeles County adults: The Adult Survey is a projectable countywide sampling of adults age 18 or older living in Los Angeles County. Households are selected using a random digit dial (RDD) sampling methodology. Within each household, interviews are conducted by telephone with one randomly selected adult. The 2007 LACHS included interviews with a total sample of 7,200 adults.
Los Angeles County children: The Child Survey is a projectable countywide sampling of Los Angeles County children ages 0-17. The survey is conducted by telephone with the child’s parent or primary caregiver (typically the mother) who lives in the same household as the child. The 2007 survey included interviews with a countywide sample of 5,288 parents/caregivers. The sample frame for the 2007 LACHS included Los Angeles County households, defined as including all houses, apartments, and mobile homes occupied by individuals, families, multiple families or extended families or occupied by multiple unrelated persons with access to a residential (landline) telephone. Excluded from this definition are communes, convents, shelters, halfway houses or dormitories, institutionalized persons, such as those living in prisons, jails, juvenile detention facilities, psychiatric hospitals, military barracks, residential treatment programs and nursing homes for the disabled or aged, the homeless, as well as households without access to a landline telephone. Statistical weighting procedures were employed in the data processing phases of both the Adult Survey and the Child Survey to reduce any biases associated with the exclusion of households without telephones or without access to a landline telephone.
LACHS is conducted every 2 to 3 years. All data collection for the 2007 LACHS, for example, was completed April 3, 2007 through January 22, 2008. Interviewing for the Adult Survey and Child Survey began simultaneously at the start of the data collection period on April 3, 2007. Interviewing on the Adult Survey was completed on December 29, 2007, while interviewing on the Child Survey was completed on January 22, 2008.
Process and Outcome
The LACHS ultimately aims to improve the health of LA County adults and children by providing program planners, policy makers, and health advocates the data they need to inform their efforts and drive change. The LACHS collects data on myriad health indicators that are used by partners within and outside the Department of Public Health as performance measures and population indicators. It is impossible to list all of the objectives and performance measures for which the LACHS provides data, but we include here a few:
Objective 1: Outreach efforts need to address the perceptions among some uninsured families that health insurance is not needed or that it may be linked to immigration status.
Objective 2: Strengthen the safety net though increased access to health care in communities where people live.
Objective 3: Improve Diet and Nutrition/Reduce Overweight among Children As far as process evaluation, we measure the success of the LACHS through a few performance measures:
Response rate for the survey
Cooperation rate for the survey
Use of LACHS data by partners within and outside of DPH
Involvement of stakeholders in planning of Health Assessment Unit reports on LACHS data
Using response rates and cooperation rates to measure the success of the LACHS allows us to gauge the efficiency and representativeness of the survey. However, the LACHS, like other telephone surveys, faces major challenges inherent to its design. Response rates to phone surveys are declining nationwide, and they are lowest in urban areas like LAC. Preliminary analyses from 2011 data collection reveal an increase in our response and cooperation rates from the previous cycle, so we hope that our collection of representative data for the LA County population will be sustainable and that our measures will reflect this.
Objective 1: Outreach efforts need to address the perceptions among some uninsured families that health insurance is not needed or that it may be linked to immigration status. Data from the survey were used to justify the need for and establishment of Public Private Partnerships to increase access to health care in communities throughout the County. In the San Fernando Valley, for example, the Consortium of Safety Net Providers were successful in obtaining over $2.4 million “H-CAP” (Healthy Communities Access Program Grant) funds from HRSA to support health care services for uninsured people. While we do not have information to calculate the total dollar amount, data from the Survey have been used to complete other H-CAP grant applications and required information for Federally Qualified Health Center (FQHC) applications.
Objective 2: Strengthen the safety net though increased access to health care in communities where people live. Data from the Survey have been used to quantify need, and to secure “safety net” health care services provided by public and private organizations throughout the County. Data from the Survey were used to obtain the original Medicaid 1115 Waiver and justify the 5-year extension of the Waiver. The Survey results are currently being used by the Department in its health care services planning. The results underscore the need for services that address cardiovascular disease and associated risks (e.g., hypertension, obesity, hyperlipidemia), diabetes, depression and other mental health conditions, alcohol and other drug abuse, and violence and unintentional injuries.
Objective 3: Improve Diet and Nutrition/Reduce Overweight among Children The Survey’s findings led to the multiple policy recommendations and actions on the part of the LA Collaborative for Healthy Active Children, representing nearly 100 organizations. The Collaborative made several policy recommendations at the school district, County, State and Federal levels. For example, because food insecurity impacted families up to 300% of the federal poverty level, it was recommended that the state and federal programs eliminate the “reduced-price” category in favor of free lunch program for all low-income students. The Collaborative launched the Healthy Breakfast Campaign, which included several components, including a media campaign to promote eating a healthy breakfast, the development of a teacher tool kit to conduct education about healthy breakfasts in the classroom, and assisting school districts as they work to reduce child hunger and improve nutrition within schools. Examples of more findings and actions to reduce and prevent overweight and obesity: Four separate LA Health briefs chronicled trends and patterns of overweight in the County, and recommended policy and programmatic action to reverse the epidemic of childhood and adult overweight. Major changes in nutrition policies have occurred in school systems in the County, perhaps most notably in LAUSD with the ban of soda machines on campuses. The Survey results have also been used extensively by the Physical Activity and Nutrition Task Force to support their policy recommendations, including the provision of healthy foods in vending machines in County facilities and creating increased opportunities for physical activity throughout LA County. The Survey results were used by the LA Health Collaborative to identify two geographic areas (in Long Beach and the Northeast San Fernando Valley) for community-wide interventions to address obesity and diabetes.
We hope that there is sufficient stakeholder commitment to sustain the survey. An advantage of designing and implementing a local health survey is that DPH maintains flexibility to ensure that the survey meets the particular data needs of LAC County, which helps to keep our stakeholders involved. For example, the successful partnership between the LA County Health Survey and First 5 LA is evidenced by the award of Research Partnership grants (in 2002, 2004, 2007 and 2010), which were specifically provided to support the Survey and explicitly to show the value of the strategic linkage between the Survey and First 5 LA’s initiatives. Data from the survey are being used in planning efforts for First 5 LA’s strategic plan as well as their “accountability framework”, which is designed to focus on measured results. However, the financial crisis of the last few years, which has strongly impacted the public sector, threatens the sustainability of the LACHS. Our funders rely on federal and state grants and contracts that may not be sustained in the current fiscal environment. The funds to continue high quality data collection, therefore, are not assured.
The dependence on soft money to fund LACHS data collection presents significant challenges. Funders are not able to guarantee monies from one survey cycle to the next due to fluctuations in their own funding, competing needs, and the timing of their grant cycles. We hope that future contributions from LA County Public Health programs and First 5 LA will match or exceed those provided for the 2011 LACHS. We will examine other revenue sources, such as new grants, to meet the budgetary goals for the next LACHS.