Views and Experiences with End-of-Life Medical Care in the U.S.
The Kaiser Family Foundation/The Economist Four-Country Survey on Aging and End-of-Life Medical Care was conducted among nationally representative random digit dial (RDD) telephone (landline and cell phone) samples of adults ages 18 and older, living in the United States (including Alaska and Hawaii), Brazil, Italy, and Japan (Note: persons without a telephone could not be included in the random selection process). SSRS carried out the sampling and weighting for all countries, and conducted computer-assisted telephone interviews for the U.S. sample. Interviews in Brazil were carried out by Cido International, and interviews in Japan and Italy were carried out by European Field Group, under the direction of SSRS. RDD landline and cell phone samples were provided by Marketing Systems Group (MSG) for the U.S., Sample Answers for Brazil, and Sample Solutions Europe (SSE) for Japan and Italy. Interview languages, field dates, and sample sizes for each country are shown in the table below. Teams from The Economist and the Kaiser Family Foundation worked together to develop the survey questionnaire and analyze the data. The Kaiser Family Foundation paid for the fieldwork costs associated with the survey. Each organization is responsible for its content.
Due to the multi-national design, the questionnaire was tested and translated in multiple stages. The first step involved a live-interview telephone pretest of the English questionnaire with U.S. respondents. Revisions to the English questionnaire were made following the pretest in order to shorten the survey instrument and improve respondent comprehension of questions. Following the English pretest, the questionnaire was translated into Spanish (for interviewing in the U.S.), Italian, Japanese, and Portuguese. Translations were reviewed by a team of professional translators and by regional experts at The Economist. A second pretest was conducted in Italy, Japan, and Brazil, after which further revisions were made to the non-English versions of the questionnaire.
In each country, to randomly select a household member for the landline samples, respondents were selected by asking for the adult male or female currently at home who had the most recent birthday based on a random rotation. If no one of that gender was available, interviewers asked to speak with the adult of the opposite gender who had the most recent birthday. For the cell phone samples, interviews were conducted with the adult who answered the phone.
Multi-stage weighting processes were applied separately for each country to ensure an accurate representation of each country’s national adult population. The first stage of weighting involved corrections to account for the fact that respondents with both a landline and cell phone have a higher probability of selection. The second weighting stage was designed to make demographic adjustments to the sample to match national population estimates. In the U.S., the sample was balanced to match known adult-population parameters using data from the Census Bureau’s 2015 March supplement of the Current Population Survey (CPS) and phone use parameters from the July-December 2015 early release estimates for the National Health Interview Survey. The weighting parameters used for the U.S. were age, gender, education, race/ethnicity, marital status, census region, and telephone use. In Italy, the sample was balanced using estimates from Instituto Nazionale di Statistica’s population projections based on 2010-2011 Census reports, with weighting parameters for age, education, region, and region by density. In Japan, the sample was balanced to match population parameters from Japan’s Statistical Yearbook 2015, based on age, education, and region by prefecture. In Brazil, the sample was balanced using the 2010 Population Census conducted by Instituto Brasileiro de Geografia de Estatística, based on age, education, region, and rural status. All statistical tests of significance account for the effect of weighting.
At the end of the field period, SSRS completed several data validation processes on the international data that included: internal validity checks, testing for straightlining, and analyzing paradata (interviewer workload, interview length, interview time, and overlap of interviews). The Kaiser Family Foundation, along with SSRS, also conducted a percent-match procedure to identify cases that share a high-percentage of identical responses to a large set of questions. This extra validation measure allows for detection of possible duplicate data, whether as a result of intentional falsification, or due to errors in data-processing.
The margin of sampling error including the design effect for each country sample is plus or minus 4 percentage points. For results based on subgroups, the margin of sampling error will be higher; sample sizes and margins of sampling error for subgroups are available by request. Note that sampling error is only one of many potential sources of error in this or any other public opinion poll. Kaiser Family Foundation public opinion and survey research is a charter member of the Transparency Initiative of the American Association for Public Opinion Research.
|Country||Field dates||Language(s)||Total sample size (unweighted)||Cell phone sample||Landline sample||M.O.S.E|
|U.S||March 30-May 29||English and Spanish||1,006||739||268||±4 percentage points|
|Italy||September 15-October 3||Italian||1,000||600||400||±4 percentage points|
|Japan||September 10-October 20||Japanese||1,000||500||500||±4 percentage points|
|Brazil||August 26-November 12||Portuguese||1,233||714||519||±4 percentage points|