Background: The most commonly used measures of association in cross-sectional studies are the odds ratio (OR) and the prevalence ratio (PR). Some cross-sectional epidemiologic studies describe their results as OR but use the definition of PR.
What is an example of a cross sectional survey?
Cross-Sectional Surveys. Cross-sectional surveys assess the prevalence of disease and the prevalence of risk factors at the same point in time and provide a "snapshot" of diseases and risk factors simultaneously in a defined population. For example, US government agencies periodically send out large surveys to random samples of the US population, asking about health status and risk factors and ...
What is cross sectional survey?
The cross-sectional survey measures smoking, smokeless tobacco use, cessation, secondhand smoke exposure, economics, media, as well as knowledge, attitudes and perceptions towards tobacco use. It is designed to produce national and regional estimates based ...
What is a cross-sectional study?
In medical research and social science, a cross-sectional study (also known as a cross-sectional analysis, transverse study, prevalence study) is a type of observational study that analyzes data from a population, or a representative subset, at a specific point in time—that is, cross-sectional data.
What is cross sectional research?
Some of the key characteristics of a cross-sectional study include: 1
- The study takes place at a single point in time
- It does not involve manipulating variables
- It allows researchers to look at numerous characteristics at once (age, income, gender, etc.)
- It's often used to look at the prevailing characteristics in a given population
- It can provide information about what is happening in a current population
Can cross-sectional studies show association?
Descriptive/analytical cross-sectional studies are useful for establishing preliminary evidence for a causal relationship. These studies are also useful for examining the association between exposure and disease onset for chronic diseases where researchers lack information on time of onset.
What are the measures of association?
Examples of measures of association include risk ratio (relative risk), rate ratio, odds ratio, and proportionate mortality ratio.
What is the most important measure from a cross-sectional study?
Cross-sectional studies measure the cause (exposure) and the effect (disease) at the same point in time. They compare the rates of diseases or symptoms of an exposed group with an unexposed group. Strictly speaking, the exposure information is ascertained simultaneously with the disease information.
What measure of association is used in a cohort study?
relative riskThe relative risk is the measure of association for a cohort study. It tells us how much more likely (or less likely) it is for people exposed to a factor to develop a disease compared to people not exposed to the factor.
What is measure of association in research?
Measures of association refers to a wide variety of statistics that quantify the strength and direction of the relationship between exposure and outcome variables, enabling comparison between different groups. The measure calculated depends on the study design used to collect data.
Is Chi square a measure of association?
The chi-square test for association (contingency) is a standard measure for association between two categorical variables. The chi-square test, unlike Pearson's correlation coefficient or Spearman rho, is a measure of the significance of the association rather than a measure of the strength of the association.
What type of data are typically used to conduct a cross-sectional study?
What is a cross-sectional study? A cross-sectional study is a type of observational research that analyzes data of variables collected at one given point in time across a sample population or a pre-defined subset. This study type is also known as cross-sectional analysis, transverse study, or prevalence study.
How do you collect data from a cross-sectional study?
Cross-sectional data can be collected by self-administered questionnaires. Using these instruments, researchers may put a survey study together with one or more questionnaires measuring the target variable(s).
What is a cross-sectional study in qualitative research?
A cross-sectional study is a type of observational study, or descriptive research, that involves analyzing information about a population at a specific point in time. Typically, these studies are used to measure the prevalence of health outcomes and describe characteristics of a population.
Is prevalence a measure of association?
Odds ratio (OR), risk ratio (RR), and prevalence ratio (PR) are some of the measures of association which are often reported in research studies quantifying the relationship between an independent variable and the outcome of interest.
Is odds ratio a measure of association?
The odds ratio is the “measure of association” for a case-control study. It quantifies the relationship between an exposure (such as eating a food or attending an event) and a disease in a case-control study.
What is the absolute measure of association?
Absolute measures of association, such as risk difference, prevalence difference, and incidence rate difference, quantify excess risk, prevalence, or rate of disease in the exposed group compared to the unexposed group.
What are the three most common measures of association?
Common measures of association include the risk difference, risk ratio, rate ratio and odds ratio.
What is the measure of association and effect?
A measure of association quantifies the relationship between exposure (i.e. risk factor) and outcome (i.e. mortality or morbidity). This is necessary in ascertainment of causes and effect and to test hypothesis about causal relationships.
Is correlation A measure of association?
Correlation is a measure of association that tests whether a relationship exists between two variables. It indicates both the strength of the association and its direction (direct or inverse). The Pearson product-moment correlation coefficient, written as r, can describe a linear relationship between two variables.
How is the strength of an association measured?
Therefore, ratio measures such as the prevalence ratio, the risk ratio, the rate ratio and the odds ratio are commonly used as measures of strength of association in epidemiological studies.
Descriptive
A cross-sectional survey may be purely descriptive and used to assess the burden of a particular disease in a defined population.
Analytical
Analytical cross-sectional surveys may also be used to investigate the association between a putative risk factor and a health outcome.
Applications of Cross-sectional studies
Cross-sectional studies are relatively easy and inexpensive to conduct and are useful for investigating exposures that are fixed characteristics of individuals, such as ethnicity or blood group.
Limitations of Cross-sectional studies
Difficult to determine whether the outcome followed exposure in time or exposure resulted from the outcome.
What is cross sectional study?
Cross-sectional studies measure the prevalence of conditions or characteristics of people in a population at a point in time or over a short period. Although they are essentially descriptive studies, their results can often suggest causative or risk factors associated with particular illness or behavior; for instance, ...
How do cross sectional studies measure the outcome of a population?
Cross-sectional studies or surveys measure both the exposure and outcome in a sample of the population at a point in time. Ideally, the sample should be randomly selected from the population. Here, a matter of concern is the proportion of selected individuals who refuse to participate, since they are almost certainly dissimilar in some way from those who consent. The larger the refusal rate, the greater the likelihood of response bias within the sample. Analysis of such studies should always report the number of eligible individuals who were initially selected and approached and what proportion of them enrolled in the study.
Why are cross sectional surveys useful?
Since temporality of association is a strong criterion for causality, cross-sectional studies cannot prove causality but help to generate causal hypotheses. Cross-sectional surveys of representative samples are useful in the assessment of healthcare needs of the population and are often used by countries and regions for this purpose. Repeated surveys can provide important information regarding health trends.
Why are cross sectional studies important?
Cross-sectional studies are useful in planning public health interventions. A population or group can be studied in a variety of ways: by questionnaire, by taking measurements (such as blood pressure), by analyzing blood specimens (e.g., for blood cholesterol levels), or by examining health care records [71].
Is it necessary to do a cross sectional study?
In cross-sectional studies, it is not always necessary to investigate the whole population: a sample is usually sufficient, provided that the individuals in the sample are representative of the total group under consideration. Cross-sectional studies are useful in planning public health interventions.
Can cross sectional studies tell us anything about a disease?
While cross-sectional studies can provide information on things like the prevalence of a particular disease (how common it is), they cannot tell us anything about the cause of a disease or what the best treatment might be [72]. They are rarely used in studies of cancer causation or prevention. View chapter Purchase book.
What is cross sectional study?
Cross-sectional studies are observational studies that analyze data from a population at a single point in time. They are often used to measure the prevalence of health outcomes, understand determinants of health, and describe features of a population.
Why are cross sectional studies important?
They are usually inexpensive and easy to conduct. They are useful for establishing preliminary evidence in planning a future advanced study.
What is the preferred measure of association in cross-sectional studies?
For chronic disease studies or studies of long-lasting risk factors, POR is the preferred measure of association in cross-sectional studies. For acute disease studies, PR is the preferred measure of association. If the prevalence of disease is low, i.e. 10% or less in exposed and unexposed populations, POR = PR. Since cross-sectional studies are particularly useful for investigating chronic diseases (e.g. prevalence of AIDS) where the onset of disease is difficult to determine, or for studying long lasting risk factors (such as smoking, hypertension, and high fat diets), the prevalence odds ratio will generally be the preferred measure of association.
What is antecedent-consequent bias?
Cross-sectional studies as well as case-control studies are affected by the antecedent-consequent bias, similar to the chicken and egg question (i.e. “which came first?”). This bias occurs when it cannot be determined that exposure preceded disease, since both are ascertained at the same time (unlike cohort studies or clinical trials). Antecedent-consequent bias does not affect cohort studies because subjects in cohort studies are selected for study because they are disease-free. Exposure is actually observed to precede disease only in a cohort design, including randomized trials.
Is exposure of interest and outcome of interest measured at the same time?
measurement of exposure of interest and outcome of interest is carried out at the same time (e.g. obesity and hypertension )
Is there control over sample size for each exposure by disease subclass?
No control over sample size for each exposure by disease subclass
Why are cross sectional analytic subjects selected?
Analytic Studies: cross sectional analytic Subjects selected because they were present at the time of the study. Selection is NOT on the basis of either exposure or outcome. Example: Does being overweight cause arthritis? This could be examined in a study in which both weight and arthritis symptoms are measured at the same time SYDNEY SYDNEY MEDICAL SCHOOL
What is case control in analytic studies?
Analytic studies - case control Subjects selected on presence [cases] or absence [controls] of the outcome factor Then exposure factor[s] is measured in cases and controls [ie after outcome is known]. Relative frequency of the exposure in cases and controls is compared. SYDNEY SYDNEY MEDICAL SCHOOL
What is an analytical study?
Analytic studies Analytic studies are used to work out the answers to questions about cause and effect: "What caused this?" Does this intervention work?' "Is this test better than another test?' Analytic studies allow you to analyse the relationship between two factors: exposure and outcome treatment and outcome test and disease SYDNEY SYDNEY MEDICAL SCHOOL
What is the measure of incidence?
Incidence CUMULATIVE INCIDENCE # of individuals experiencing a NEW event during a time period # of susceptible individuals at the beginning of the time period Incidence is a measure of events (event rate) Incidence is a measure of risk SYDNEY SYDNEY MEDICAL SCHOOL
