How to Use Simplified Reproductive Calendar Data from the Demographic and Health Survey.

IPUMS Demographic and Health Surveys (IPUMS DHS), through its intuitive website (http://dhs.ipums.org/), eliminate barriers to overtime and cross-national analyses with the DHS. IPUMS DHS recently released simplified reproductive calendar data. These calendar data are harmonized across samples, distinguish "not in universe" cases from "no" responses, and do not require destringing. Variable names are hot links to important documentation, such as survey-question text and comparability concerns. Analysts can also select consistently coded variables relating to the woman, her household, and her social and environmental context without merging files.

Contextual Data in IPUMS DHS: Physical and Social Environment Variables linked to the Demographic and Health Surveys.

The Demographic and Health Surveys (DHS) are the most important source of comparative information on the health of women and young children in low- and middle-income countries and are well-suited for studies of the relationship between environmental factors and health. However, barriers have limited the use of the DHS for these purposes. IPUMS DHS, an online data dissemination tool, overcomes these barriers, simplifying comparative analyses with DHS. IPUMS DHS recently incorporated environmental variables that can easily be attached to individual or household records, facilitating the use of DHS data for the study of population and environment issues. We provide a brief introduction to IPUMS DHS, describe the current and anticipated environmental variables and how to use them, and provide an example of the novel research possibilities facilitated by this latest IPUMS DHS development. IPUMS-DHS is available free online at dhs.ipums.org.

Use of the integrated health interview series: trends in medical provider utilization (1972-2008).

The Integrated Health Interview Series (IHIS) is a public data repository that harmonizes four decades of the National Health Interview Survey (NHIS). The NHIS is the premier source of information on the health of the U.S. population. Since 1957 the survey has collected information on health behaviors, health conditions, and health care access. The long running time series of the NHIS is a powerful tool for health research. However, efforts to fully utilize its time span are obstructed by difficult documentation, unstable variable and coding definitions, and non-ignorable sample re-designs. To overcome these hurdles the IHIS, a freely available and web-accessible resource, provides harmonized NHIS data from 1969-2010. This paper describes the challenges of working with the NHIS and how the IHIS reduces such burdens. To demonstrate one potential use of the IHIS we examine utilization patterns in the U.S. from 1972-2008.

A Half Century of Health Data for the U.S. Population: The Integrated Health Interview Series.

The U.S. National Health Interview Survey (NHIS) is the world's longest survey time series of health data and a rich source of information on health conditions, behaviors, and care from the 1960s to the present. NHIS public-use files are difficult to use for long-term analysis, due to complex file structure, changes in questionnaire content, and evolving variable names and coding schemes. Researchers at the Minnesota Population Center have created the Integrated Health Interview Series (IHIS) to overcome these problems. IHIS provides access to thousands of consistently coded and well-documented NHIS variables on the Internet and makes it easy to analyze health trends and differentials. IHIS multiplies the value of NHIS data by allowing researchers to make consistent comparisons over half a century and thus to study U.S. health status as a dynamic process. This article describes the main features of IHIS and suggests fruitful avenues for historical research using these invaluable health data.

Big Data: Large-Scale Historical Infrastructure from the Minnesota Population Center.

The Minnesota Population Center (MPC) provides aggregate data and microdata that have been integrated and harmonized to maximize crosstemporal and cross-spatial comparability. All MPC data products are distributed free of charge through an interactive Web interface that enables users to limit the data and metadata being analyzed to samples and variables of interest to their research. In this article, the authors describe the integrated databases available from the MPC, report on recent additions and enhancements to these data sets, and summarize new online tools and resources that help users to analyze the data over time. They conclude with a description of the MPC's newest and largest infrastructure project to date: a global population and environment data network.

Four decades of population health data: the integrated health interview series as an epidemiologic resource.

The National Health Interview Survey (NHIS) is a primary source of information on the changing health of the US population over the past 4 decades. The full potential of NHIS data for analyzing long-term change, however, has rarely been exploited. Time series analysis is complicated by several factors: large numbers of data files and voluminous documentation; complexity of file structures; and changing sample designs, questionnaires, and variable-coding schemes. We describe a major data integration project that will simplify cross-temporal analysis of population health data available in the NHIS. The Integrated Health Interview Series (IHIS) is a Web-based system that provides an integrated set of data and documentation based on the NHIS public use files from 1969 to the present. The Integrated Health Interview Series enhances the value of NHIS data for researchers by allowing them to make consistent comparisons across 4 decades of dramatic changes in health status, health behavior, and healthcare.