3. Research Methods in Aging Flashcards
Includes chapter 3
what different research methods can be used for adult development and aging?
- experimental designs
- quasi-experimental designs
- correlational designs
- cross-sectional
- longitudinal
- prospective
- sequential
what are the characteristics of an experimental design?
- there are two or more conditions
- everything is held constant except the IV
- there is some sort of manipulation or treatment
what are the benefits and disadvantages of using the experimental method?
benefits
- ability to make causal claims
- examine interactions with age (2 IVs)
- ex. age differences in recall of memories for different stimuli
disadvantages
- cannot examine whether aging causes changes
- but can test whether certain things impact people who are old
- can’t randomly assign age
what are the characteristics of a quasi-experimental design?
- subjects are not randomly assigned to conditions
- subjects are selected based on pre-existing values of the independent variable
what are the benefits and disadvantages of using the quasi-experimental method?
benefits
- allows researchers to examine the effect of some “treatment” that may not be ethical or logistically possible
disadvantages
- has less internal validity than experiments
- can’t determine if aging causes changes
what are the characteristics of a correlational design?
- a type of non-experiment
- measure 2 or more different variables in a sample
- how co-related are the variables?
- how strongly is one associated with the other?
- variables need to be continuous and not grouped
what is a bivariate correlation?
- a statistic that indexes the degree of relationship between two continuous variables
- +/- = direction of relationship
- number = strength of the relationship
what are the benefits and disadvantages of using the correlational method?
benefits
- describes the relationship between two variables
- ex. age and reaction time
disadvantages
- cannot infer causation
- only useful for linear relationships
- doesn’t tell us about any one individual
- cohort and time of measurement effects
what are the different types of descriptive statistics?
- cross sectional (age differences)
- longitudinal (age changes)
- sequential
what are age effects?
- differences caused by underlying processes that occur with aging (biological/psychological)
- what researchers are interested in
what are cohort effects?
- differences caused by experiences and circumstances unique to the generation to which one belongs
- normative, history graded influences
what are time of measurement effects?
- differences stemming from sociocultural, environmental, historical, or other events at the time of data collection
- might impact responses of participants and possibly create a cohort effect seen in the future
what are the characteristics of cross sectional research designs?
- measure multiple age groups at one time
- don’t know why groups differ, just know whether they do or don’t differ
- subject to cohort effects
- key to controlling for cohort differences is for researchers to select younger samples comparable in important ways to the older sample
what is task equivalence and why is it important?
- different age groups may very well react differently to the test materials, causing performance differences to be an artifact of the design
- need to take this into account when choosing research design
what are the benefits and disadvantages of cross sectional research designs?
benefits
- examine age differences in some variable of interest
- fast and usually cheap
- addresses time of measurement effects (kind of)
- we are comparing groups to each other, they all experience the same thing at the same time
- the latest and most up‐to‐date technology can be used
disadvantages
- it may not be representative
- will the 60 year old we measured today have the happiness level of the 90 year olds in 30 years?
- doesn’t examine age change
- doesn’t account for cohort effects
- often use extreme age groups
what are the characteristics of a longitudinal research design?
- follow the same group of people over some period of time
- period of time depends on variables of interest
- cognitive development timeline differs for children vs. adults
- still can’t say if it is an age effect because it doesn’t account for time of measurement effect
what is a prospective study?
researchers sample from a population of interest before they develop a particular type of illness or experience a particular type of life event
what is selective attrition?
- participants who drop out of a longitudinal study are not necessarily representative of the sample that was originally tested
- non-random loss of participants; death, illness, etc
what is terminal decline?
- individuals gradually lose cognitive abilities as they draw closer to death
- pull down group averages, and when they drop out the averages go up again
- shows improvement where there isn’t any
what are the benefits and disadvantages of longitudinal research design?
benefits
- allows assessment of actual changes as individuals age
- prospective longitudinal designs: watches for outcomes during the study to examine suspected risk/protective factors
disadvantages
- time of measurement and age confounded
- don’t know if it is generalizable to other cohorts
- attrition - some people drop out, die, move away, lose interest
- sick people might drop out, so the happiness average is higher than it should be
- time consuming and expensive
- measures/technology may change
- researcher’s interest/capacity
- progression of knowledge
what are the characteristics of a sequential research design?
- includes a cross-sectional study conducted at two or more times of measurement
- includes two or more longitudinal designs that represent two or more cohorts
- additional intake adds new cohorts and addresses attrition
- addresses time of measurement effect and cohort effect
- can be used to compare birth cohorts and timepoint cohorts
what is the Most Efficient Design?
- set of three designs manipulating the variables of age, cohort, and time of measurement
- it enables the most amount of information to be condensed into the most inclusive data framework
what are the three designs in the Most Efficient Design?
- time sequential - data are organized by age and time of measurement
- cohort sequential - cohorts are compared at different ages
- cross sequential - cohorts are examined at different times of measurement
what are the benefits and disadvantages of sequential research design?
benefits
- can examine possible cohort effects
- permits different types of comparisons to be made
- examine and control possible confounding of effects
disadvantages
- attrition (selective?)
- time consuming & expensive
- possible practice effects
- measures/technology
- researchers
- progression of knowledge
what are the different types of research methods?
- laboratory studies
- qualitative studies
- archival research
- epidemiological studies
- case reports
- focus groups
- daily diaries
- observational methods
- meta-analyses
what are epidemiological studies?
- epidemiology - study of the distribution and determinants of health‐related states or events
- an epidemiological study may use survey methodology asking about a particular disease
- finds prevalence and incidence statistics
- prevalence statistics - provide estimates of the percentage of people who have ever had symptoms in a particular period
- incidence statistics - provide estimates of the percentage of people who first develop symptoms in a given period
why would a researcher choose to use a focus group?
- less formal research method where a meeting of a group of respondents is oriented around a particular topic of interest
- investigator attempts to identify important themes in the discussion and keep the conversation oriented to these themes
- goal is to develop concrete research questions to pursue in subsequent studies
- particularly useful when little pre‐existing research on the topic is available
why would a researcher choose to use daily diaries?
- participants enter data on a daily basis when researchers want to examine day-to-day variations in a measure of interest
- carried out over a period of weeks or months
- researchers can track small variations in conditions that they believe may influence people’s day‐to‐day functioning
