ABSTRACT
BACKGROUND: Survey non-response rates are important quality indicators. Refusal rates can induce non-response bias in health survey estimates. However, comparisons across surveys highlight inconsistencies in the use of survey outcome categories and in the calculation of response rates. In this paper we discuss the relevance of these indicators and suggest other survey quality indicators. METHODS: Outcome rates from two French random-digit dialing (RDD) telephone surveys are compared : the Nicolle survey on infectious diseases of 4112 individuals conducted in 2006, and the HIV knowledge, attitude, belief and practices (KABP) survey of 5071 individuals in 2004. Based on the same protocol, we describe in details the way the two RDD samples were drawn and how non-response rates were estimated. RESULTS: Non-response rates were different: 36% in Nicolle survey and 18% in KABP survey. However, the quantity of telephone numbers required to obtain one interview was higher in the KABP survey: 2.8 telephone numbers versus 2.1 in the Nicolle survey. The participation rates, aggregating together refusals, break-off and non-reachable numbers, were equivalent for the two surveys. This result occurred because of a greater proportion of unreached calls in the KABP surveys, which is not integrated into the non-response rates commonly used. CONCLUSION: Survey non-response rate is insufficient to estimate the quality of a survey. The need for other indicators has been previously stressed in the literature, notably with the adoption and utilization of the American Association for Public Opinion Research (AAPOR) standard definitions of four indicators. But these indicators are quite complex for evaluating non-response bias between surveys. In addition to the classical refusal rate, two other indicators are proposed in this paper: participation rate (number of complete interviews divided by the number of eligible and of unknown eligibility units) and a liking contact rate (number of unreachable units because of a long absence, break-off or non-answer divided by the number of eligible and of unknown eligibility units). The sum of these three indicators is equal to 100% and thus easier to manipulate when comparing surveys.
Subject(s)
Communicable Diseases/epidemiology , Health Surveys , Patient Participation/statistics & numerical data , Telephone , Adolescent , Adult , Aged , Communicable Diseases/transmission , Data Interpretation, Statistical , France/epidemiology , HIV Infections/epidemiology , Health Knowledge, Attitudes, Practice , Health Surveys/standards , Humans , Middle Aged , Random Allocation , Refusal to Participate/statistics & numerical data , Sampling Studies , Selection Bias , Surveys and QuestionnairesABSTRACT
BACKGROUND: Compiling individual records which come from different sources remains very important for multicenter epidemiological studies, but at the same time European directives or other national legislation concerning nominal data processing have to be respected. These legal aspects can be satisfied by implementing mechanisms that allow anonymization of patient data (such as hashing techniques). Moreover, for security reasons, official recommendations suggest using different cryptographic keys in combination with a cryptographic hash function for each study. Unfortunately, such an anonymization procedure is in contradiction with the common requirement in public health and biomedical research as it becomes almost impossible to link records from separate data collections where the same entity is not referenced in the same way. Solving this paradox by using methodology based on the combination of hashing and enciphering techniques is the main aim of this article. METHODS: The method relies on one of the best known hashing functions (the secure hash algorithm) to ensure the anonymity of personal information while providing greater resistance to dictionary attacks, combined with encryption techniques. The originality of the method relies on the way the combination of hashing and enciphering techniques is performed: like in asymmetric encryption, two keys are used but the private key depends on the patient's identity. RESULTS: The combination of hashing and enciphering techniques provides a great improvement in the overall security of the proposed scheme. CONCLUSION: This methodology makes the stored data available for use in the field of public health for the benefit of patients, while respecting legal security requirements.
Subject(s)
Algorithms , Confidentiality/legislation & jurisprudence , Data Collection , Epidemiologic Studies , Medical Record Linkage/methods , Multicenter Studies as Topic , Data Collection/statistics & numerical data , HumansABSTRACT
PIP: In this article, translated from the original French, the author describes demographic surveys that have been carried out mostly on an ongoing basis in France.^ieng
Subject(s)
Demography , Developed Countries , Europe , France , Population , Population DynamicsABSTRACT
PIP: The author "presents an overview of [demographic] surveys conducted during the last 20 years in France."^ieng
Subject(s)
Data Collection , Demography , Family Characteristics , Marriage , Sampling Studies , Vital Statistics , Developed Countries , Europe , Family , France , Population , Population Characteristics , Population Dynamics , ResearchABSTRACT
PIP: Developments in survey techniques that have occurred in France since the end of World War II are reviewed, with an emphasis on improvements in the availability of demographic data. The author describes changes in vital statistics, the development of permanent surveys, and specific surveys carried out since 1970. Some consideration is also given to plans for future surveys. (SUMMARY IN ENG AND GER)^ieng
