Longitudinal Studies And Designs

Question 1

Longitudinal study

Answer 1

A research method that follows a specific cohort over a long periods of time. Looking at changes in variables. In order to explore developments or changes due to experiences (interventions)

Question 2

Longitudinal design

Answer 2

An experimental design, in which ppts are tested at different intervals over a long time. (Pre/post intervention). Is a form of repeated measures design.

Question 3

Why are longitudinal studies a form of repeated measures deign?

Answer 3

The same ppts are retested.

Question 4

What do longitudinal designs typical measure?

Answer 4

Measure 2 or more variables over time. Where the expected changes are due to manipulation. For instance, the IV would be the testing of diff time point in relation to a manipulation.
(Introduction of a course, therapy)

Question 5

Why are longitudinal studies and designs better than cross sectional studies?

Answer 5

Researchers can be sure that any changes are due to the passage of time and not any difference between the cohorts.

Question 6

What is a cohort?

Answer 6

A group of ppts selected at the same age or stage (life stage)

Question 7

What is a cross-sectional study?

Answer 7

Compares different groups of participants at one point in time.
To make a comparison between different ages of life stages.

Question 8

What is sample attrition?

Answer 8

When ppts from a sample drop out of a study over time.

Question 9

Why might ppts drop out of a study?

Answer 9

Ethical, boredom, life events, contact

1. Ethical: Withdraw consent (parent may have given consent)
2. Boredom: From being tested repeatedly.
3. Life events preventing participation (death, poor physical and mental health, homelessness, prison)
4. Cannot be contacted

Question 10

Form the core studies what studies are longitudinal studies/designs

Answer 10

Study: Fagen, Saavedra and Silverman
Design: Holzel
Cross sectional: The rest of the core studies

Question 11

Summarise 6 weaknesses of longitudinal studies.

Answer 11

Practical issues (time/cost)
Methods (sample attrition)
Generalisability (cohort v pop)
Temporal validity (change in norms)
Internal validity (confounding varia)
Applicability (long time before meaningful results obtained)

Question 12

Weaknesses- sample attrition (methodology)

Answer 12

Sample attrition, leads to a reduction in sample size. The consequent sample may be biased as they may have similar qualities (motivated) and if the sample becomes so small it will not generalise well.

Question 13

Weaknesses- (temporal validity)

Answer 13

Societal norms and technologies advance as time progresses making it difficult to compare results across different time periods.

Question 14

Weaknesses- practical issues/ reliability

Answer 14

Longitudinal studies require extensive time, resource and funding due to the duration of data collection and follows ups. This may cause issues for reliability as researches may need to introduce better, improved measures. Lowering consistency. The researchers (interviews) involved may not remain contant.

Question 15

Summarise the strengths of longitudinal studies

Answer 15

Good internal validity (causal relation)
Valuable insights (developments)
Large amount of data produced
Real world application

Question 16

Strengths- valuable insights

Answer 16

Can help researches distinguish between changes that happen as people develop (age affects). Recognise generational differences reflecting the context in which the cohorts grew up in (generational effects)

Question 17

Strengths (internal validity)

Answer 17

Allows researchers to establish causal relationships by observing changes over time, the use of repeated testing, consistency in measures, and limited effects of participant variables.

Question 18

Strengths- produces large amount of data

Answer 18

produces large amount of data in each ppts over time facilitating a through analysis.