What are longitudinal studies and how do they work?
What are longitudinal studies and how do they work? Longitudinal studies utilize continuous or recurring assessments to monitor specific individuals over lengthy periods of time—often years or decades—in order to gather information about them. In most cases, they are observational in nature, with quantitative and/or qualitative data being ...
What is one problem with longitudinal research?
The primary disadvantage of using longitudinal studies for research is that long-term research increases the chances of unpredictable outcomes. If the same people cannot be found for a study update, then the research ceases. Here are some additional key advantages and disadvantages of longitudinal studies to think about.
What are some limitations of longitudinal studies?
- Sample attrition – people dropping out of the study, and the people who remain in the study may not end up being representative of the starting sample.
- People may start to act differently because they know they are part of the study
- Because they take a long time, they are costly and time consuming.
What are the advantages of longitudinal studies?
What are the strengths and weaknesses of a longitudinal study?
- They are effective in determining variable patterns over time.
- They can ensure clear focus and validity.
- They are very effective in doing research on developmental trends.
- They are more powerful than cross-sectional studies.
- They are highly flexible.
What is considered a longitudinal study?
A longitudinal study, like a cross-sectional one, is observational. So, once again, researchers do not interfere with their subjects. However, in a longitudinal study, researchers conduct several observations of the same subjects over a period of time, sometimes lasting many years.
Can a longitudinal study be 3 months?
A longitudinal study is a type of correlational research study that involves looking at variables over an extended period of time. This research can take place over a period of weeks, months, or even years. In some cases, longitudinal studies can last several decades.
What are the three types of longitudinal studies?
There are a range of different types of longitudinal studies: cohort studies, panel studies, record linkage studies. These studies may be either prospective or retrospective in nature.
How do you do a longitudinal study?
Go to:Step one: Build a collaborative team and set a long-term plan. ... Step two: Develop a strong theoretical framework to support research questions. ... Step three: Design a comprehensive study that maps onto study aims. ... Step four: Determine the sample and develop a recruitment plan. ... Step five: Select and/or develop measures.
What are the limitations of longitudinal studies?
List of Disadvantages of Longitudinal StudiesThey require huge amounts of time. ... They risk gathering data that is not 100% reliable. ... They would risk experiencing panel attrition. ... They require a large sample size. ... They can be more expensive compared with cross-sectional studies.
Is longitudinal study quantitative or qualitative?
qualitative researchLongitudinal studies are primarily a qualitative research method because the researcher observes and records changes in variables over an extended period. However, it can also be used to gather quantitative data depending on your research context.
What is an example of a longitudinal research study?
What is an example of a longitudinal study? The 1970 British Cohort Study, which has collected data on the lives of 17,000 Brits since their births in 1970, is one well-known example of a longitudinal study.
What type of evidence is a longitudinal study?
Longitudinal Study follow subjects over time with continuous or repeated monitoring of risk factors or health outcomes, or both. Researchers conduct several observations of the same subjects over a period of time, sometimes lasting many years.
Can longitudinal studies be experimental?
Longitudinal-experimental studies are follow-up surveys that include an experimental intervention. The main advantage of these surveys is that it is possible to study both the natural history of development and the impact of interventions in one research project.
What is a strength of a longitudinal study?
Many of the advantages of longitudinal studies relate to the analytic questions their data can help address. For example, longitudinal data help with: Exploring patterns of change and the dynamics of individual behaviour. Longitudinal data allows researchers to explore dynamic rather than static concepts.
What type of evidence is a longitudinal study?
Longitudinal Study follow subjects over time with continuous or repeated monitoring of risk factors or health outcomes, or both. Researchers conduct several observations of the same subjects over a period of time, sometimes lasting many years.
Can a longitudinal study be experimental?
Longitudinal study designs Longitudinal research may take numerous different forms. They are generally observational, however, may also be experimental.
What is the difference between cross-sectional study and longitudinal?
Longitudinal studies differ from one-off, or cross-sectional, studies. The main difference is that cross-sectional studies interview a fresh sample of people each time they are carried out, whereas longitudinal studies follow the same sample of people over time.
What is a strength of a longitudinal study?
Many of the advantages of longitudinal studies relate to the analytic questions their data can help address. For example, longitudinal data help with: Exploring patterns of change and the dynamics of individual behaviour. Longitudinal data allows researchers to explore dynamic rather than static concepts.
What’s the difference between method and methodology?
Methodology refers to the overarching strategy and rationale of your research project . It involves studying the methods used in your field and...
What’s the difference between quantitative and qualitative methods?
Quantitative research deals with numbers and statistics, while qualitative research deals with words and meanings. Quantitative methods allow yo...
What is sampling?
A sample is a subset of individuals from a larger population . Sampling means selecting the group that you will actually collect data from in...
What’s the difference between reliability and validity?
Reliability and validity are both about how well a method measures something: Reliability refers to the consistency of a measure (whether the r...
What is the difference between internal and external validity?
I nternal validity is the degree of confidence that the causal relationship you are testing is not influenced by other factors or variables . Ext...
What is experimental design?
Experimental design means planning a set of procedures to investigate a relationship between variables . To design a controlled experiment, you ne...
What are independent and dependent variables?
You can think of independent and dependent variables in terms of cause and effect: an independent variable is the variable you think is the ca...
What is the difference between quantitative and categorical variables?
Quantitative variables are any variables where the data represent amounts (e.g. height, weight, or age). Categorical variables are any variables...
What is the difference between discrete and continuous variables?
Discrete and continuous variables are two types of quantitative variables : Discrete variables represent counts (e.g. the number of objects in a...
How long do longitudinal studies last?
Longitudinal studies can last anywhere from weeks to decades, although they tend to be at least a year long. Frequently asked questions: Methodology.
What is methodology in research?
Methodology refers to the overarching strategy and rationale of your research project. It involves studying the methods used in your field and the theories or principles behind them, in order to develop an approach that matches your objectives.
What is the degree of confidence that the causal relationship you are testing is not influenced by other factors or variables?
I nternal validity is the degree of confidence that the causal relationship you are testing is not influenced by other factors or variables.
How long does a longitudinal study last?
This research can take place over a period of weeks, months, or even years. In some cases, longitudinal studies can last several decades.
What are the different types of longitudinal studies?
There are three major types of longitudinal studies: 1 Panel study: Involves sampling a cross-section of individuals. 2 Cohort study: Involves selecting a group based on a specific event such as birth, geographic location, or historical experience. 3 Retrospective study: Involves looking to the past by looking at historical information such as medical records.
Why do researchers use longitudinal data?
Because longitudinal studies take place over a period of years (or even decades), researchers can use their data to establish a sequence of events when looking at the aging process.
Why is longitudinal research important?
This method allows researchers to look at changes over time. Because of this, longitudinal methods are particularly useful when studying development and lifespan issues.
How expensive are longitudinal studies?
Longitudinal Studies Can Be Expensive. Longitudinal studies require enormous amounts of time and are often quite expensive. Because of this, these studies often have only a small group of subjects, which makes it difficult to apply the results to a larger population.
How do researchers look at how certain things may change at different points in life?
1. For example, consider longitudinal studies that looked at how identical twins reared together versus those reared apart differ on a variety of variables.
What is longitudinal research?
Longitudinal research is often contrasted with cross-sectional research. While longitudinal research involves collecting data over an extended period of time, cross-sectional research involves collecting data at a single point in time.
Advantages
Because longitudinal studies observe variables over extended periods of time, researchers can use their data to study developmental shifts and understand how certain things change as we age.
Limitations
Longitudinal studies can take months or years to complete, rendering them expensive and time consuming. Because of this, researchers tend to have difficulty recruiting participants, leading to smaller sample sizes.
How to Perform a Longitudinal Study
When beginning to develop your longitudinal study, you have to first decide if you want to collect your own data or use data that has already been gathered.
Longitudinal vs Cross-Sectional Studies
Longitudinal studies and cross-sectional studies are two different observational study designs where researchers are analyzing a target population without manipulating or altering the natural environment in which the participants exist.
What is longitudinal study?
Study with repeated observations over time. A longitudinal study (or longitudinal survey, or panel study) is a research design that involves repeated observations of the same variables (e.g., people) over short or long periods of time (i.e., uses longitudinal data ). It is often a type of observational study, although they can also be structured as ...
How many participants are needed for a longitudinal study?
Qualitative longitudinal studies may include only a handful of participants, and longitudinal pilot or feasibility studies often have fewer than 100 participants.
Why are longitudinal studies more powerful than cross sectional studies?
However, because of the repeated observation at the individual level , they have more power than cross-sectional observational studies, by virtue of being able to exclude time-invariant unobserved individual differences and also of observing the temporal order of events. Some of the disadvantages of longitudinal study are that they are time-consuming and expensive. Therefore, they are not convenient.
Why are longitudinal studies less likely to be the result of cultural differences across generations?
The reason for this is that, unlike cross-sectional studies , in which different individuals with the same characteristics are compared , longitudinal studies track the same people, and so the differences observed in those people are less likely to be the result of cultural differences across generations.
Why are longitudinal studies important?
Longitudinal studies thus make observing changes more accurate and are applied in various other fields. In medicine, the design is used to uncover predictors of certain diseases. In advertising, the design is used to identify the changes that advertising has produced in the attitudes and behaviors of those within the target audience who have seen the advertising campaign. Longitudinal studies allow social scientists to distinguish short from long-term phenomena, such as poverty. If the poverty rate is 10% at a point in time, this may mean that 10% of the population are always poor or that the whole population experiences poverty for 10% of the time.
Where is the Raine study?
The Raine Study is based in Perth, Western Australia. It has followed the same group of pregnant women (Gen1) and their babies (Gen2) who were born into the study between 1989 and 1992. Its original aim was to investigate the benefits of more frequent ultrasound scans on infant health. It now studies the impact that early life factors (from the womb onwards) have on health throughout life. The Raine Study now includes 4 generations of cohort members.
Is longitudinal study retrospective or prospective?
Longitudinal studies can be retrospective (looking back in time, thus using existing data such as medical records or claims database) or prospective (requiring the collection of new data).
How long can a longitudinal study last?
3. Timeline: A longitudinal study can span weeks, months, years, or even decades. This dramatically contrasts what is obtainable in cross-sectional studies that only last for a short time.
When Would You Use a Longitudinal Study?
If you're looking to discover the relationship between variables and the causal factors responsible for changes, you should adopt a longitudinal approach to your systematic investigation. Longitudinal studies help you to analyze change over a meaningful time.
Why is longitudinal research considered qualitative?
Longitudinal studies are primarily a qualitative research method because the researcher observes and records changes in variables over an extended period. However, it can also be used to gather quantitative data depending on your research context.
What is longitudinal research?
A longitudinal study is a correlational research method that helps discover the relationship between variables in a specific target population. It is pretty similar to a cross-sectional study, although in its case, the researcher observes the variables for a longer time, sometimes lasting many years.
What is cross sectional study?
A cross-sectional study is a type of observational study in which the researcher collects data from variables at a specific moment to establish a relationship among them. On the other hand, longitudinal research observes variables for an extended period and records all the changes in their relationship.
What is panel study?
In a panel study, the researcher uses data collection methods like surveys to gather information from a fixed number of variables at regular but distant intervals, often spinning into a few years. It's primarily designed for quantitative research, although you can use this method for qualitative data analysis .
Why do we conduct cohort studies?
You should conduct a cohort study if you're looking to establish a causal relationship within your data sets. For example, in medical research, cohort studies investigate the causes of disease and establish links between risk factors and effects.
What is longitudinal study?
What is a Longitudinal Study? - Definition with Examples. A longitudinal study is a research conducted over an extended period of time. Learn more on how to apply this type of study and its advantages.
Why is longitudinal research considered a long term study?
Because this is a long-term study, the researchers have a flexibility that is not possible with other research formats. Additional data points can be collected to study unexpected findings, allowing changes to be made to the survey based on the approach that is detected. Disadvantages of longitudinal studies.
Why is longitudinal research important?
One of the essential reasons is, longitudinal studies give unique insights that many other types of research fail to provide.
Why do longitudinal studies follow up with cross-sectional studies?
A longitudinal study may follow up on a cross-sectional study to investigate the relationship between the variables more thoroughly.
Why do longitudinal studies involve the same subjects over a long period of time?
Because longitudinal studies involve the same subjects over a long period of time, what happens to them outside of data collection times can influence the data that is collected in the future. Some people may decide to stop participating in the research. Others may not be in the correct demographics for research.
How many variables can be used in longitudinal studies?
In longitudinal studies, only one variable can be
What is retrospective study?
While doing a retrospective study, the researcher uses an administrative database, pre-existing medical records, or one-to-one interviews. Advantages and disadvantages of conducting longitudinal surveys. As we’ve demonstrated, a longitudinal study is useful in science, medicine, and many other fields.
Can you draw conclusions from one survey?
A survey is like a snapshot: From one survey, you can only draw conclusions about a single time, place, and group of people. And often, that’s all you need to know. But sometimes, you also want to understand how the people you surveyed are changing. In that case, one single survey, or snapshot, is not enough—so we need to repeat surveys in order ...
Can you run a decades long survey?
While you may not be in the market for running a decades-long study anytime soon, you can benefit from repeating surveys and tracking changes in your respondents’ attitudes and behaviors over time. (By the way—when you survey the same people time and time again, you’re running what’s also called a panel survey.)
What are the advantages of a longitudinal study?
Longitudinal studies and longitudinal surveys offer some major benefits over cross-sectional studies. Some of the main advantages are:
What is longitudinal research?
A longitudinal study or a longitudinal survey (both of which make up longitudinal research) is a study where the same data are collected more than once, at different points in time. The purpose of a longitudinal study is to assess not just what the data reveal at a fixed point in time, but to understand how (and why) things change over time.
Why do people drop out of longitudinal studies?
Drop out – because longitudinal studies often take place over many years, there is a very real risk that respondents drop out over the length of the study. This can happen for any number of reasons (for examples, people relocating, starting a family, a new job, etc) and can have a very detrimental effect on the study.
Why are longitudinal studies at risk of recall bias?
Bias – because longitudinal studies capture current data at multiple points in time, they are at lower risk of recall bias. In other words, there’s a lower chance that people will forget an event, or forget certain details about it, as they are only being asked to discuss current matters. What are the disadvantages of.
Why are longitudinal studies more expensive?
Cost – compared to cross-sectional studies, longitudinal studies are typically substantially more expensive to execute, as they require maintained effort over a long period of time.
What is the difference between longitudinal and cross sectional?
13, 14, 15, 16, 17 and 18) are all different people (obviously!) with different life experiences – whereas, in the longitudinal group, each the data at each age point is generated by the same group of people (for example, John Doe will complete a survey at age 13, 14, 15, and so on).
How long do longitudinal studies follow up?
At the other extreme, some longitudinal studies follow up relatively small groups for a few days or weeks. Thus, firemen acutely exposed to noxious fumes might be monitored to identify any immediate effects. Most longitudinal studies examine associations between exposure to known or suspected causes of disease and subsequent morbidity or mortality.
How are longitudinal studies conducted?
In a longitudinal study subjects are followed over time with continuous or repeated monitoring of risk factors or health outcomes, or both. Such investigations vary enormously in their size and complexity. At one extreme a large population may be studied over decades. For example, the longitudinal study of the Office of Population Censuses and Surveys prospectively follows a 1% sample of the British population that was initially identified at the 1971 census. Outcomes such as mortality and incidence of cancer have been related to employment status, housing, and other variables measured at successive censuses. At the other extreme, some longitudinal studies follow up relatively small groups for a few days or weeks. Thus, firemen acutely exposed to noxious fumes might be monitored to identify any immediate effects.
What is the case fatality rate?
Case fatality rate (the proportion of episodes of illness that end fatally) describes the short term outcome of a disease, but must be interpreted with caution. An episode of illness does not correspond to a fixed time interval.
Why is it important to define precisely how subjects are selected for study?
For the findings of a clinical follow up study to be generalised to patients elsewhere , it is important to define precisely how subjects are selected for study. For example, patients presenting with asthma to a respiratory physician are likely to have a different prognosis from those seen in general practice.
Can asthma be measured retrospectively?
Obviously, such a study is only feasible when the health outcome of interest can be measured retrospectively. Mortality and cancer incidence can usually be ascertained reliably, but disorders such as asthma may be harder to assess in retrospect.
Summary
Purpose
- So why would researchers want to conduct studies that take a very long time to complete? One reason is that a longitudinal study can be used to discover relationships between variables that are not related to various background variables. This observational research technique involves studying the same group of individuals over an extended period. So what are some of the reaso…
Analysis
- Data is first collected at the outset of the study, and may then be repeatedly gathered throughout the length of the study. Doing this also allows researchers to observe how variable may change over time.
Example
- For example, imagine that a group of researchers is interested in studying how exercise during middle age might impact cognitive health as people age. The researchers hypothesize that people who are more physically fit in their 40s and 50s will be less likely to experience cognitive declines in their 70s and 80s.
Benefits
- The benefit of this type of research is that it allows researchers to look at changes over time. Because of this, longitudinal methods are particularly useful when studying development and lifespan issues. Researchers can look at how certain things may change at different points in life and explore some of the reasons why these developmental shifts take place.
Applications
- An example of how this research can be used include longitudinal studies that look at how identical twins reared together versus those reared apart differ on a variety of variables. Researchers track these participants from childhood into adulthood to look at how growing up in a different environment influences things such as personality and achievement.
Advantages
- As with other types of psychology research, longitudinal studies have both their strengths and weaknesses. There are some important advantages to conducting longitudinal research, but there are also a number of drawbacks that need to be considered.
Risks
- Longitudinal studies require enormous amounts of time and are often quite expensive. Because of this, these studies often have only a small group of subjects, which makes it difficult to apply the results to a larger population. Another problem is that participants sometimes drop out of the study, shrinking the sample size and decreasing the amount of data collected.
Causes
- This tendency for some participants to be more likely to drop out of a study is known as selective attrition. In our example above, participants might drop out for a number of reasons. Some might move away from the area while others simply lose the motivation to participate. Others might become housebound due to illness or age-related difficulties, and some participants will pass a…
Criticisms
- In some cases, this can lead to an attrition bias and influence the results of the longitudinal study. If the final group no longer reflects the original representative sample, this attrition can also threaten the validity of the experiment. Validity refers to whether or not a test or experiment accurately measures what it claims to measure. If the final group of participants is not a represe…
Significance
- A longitudinal study can provide a wealth of information on a topic. Such studies can be expensive, costly, and difficult to carry out, but the information obtained from such research can be very valuable.