3. Longitudinal studies and Interventions Flashcards
Cross-sectional/correlational studies measure…
Two or more things at the same point in time
Longitudinal studies measure… and see how it…
One thing now
Predicts something at a later point in time
Longitudinal studies don’t tell us about direct causation, but they do provide stronger evidence about causation. This is because of a temporal assumption. What does this mean?
That cause must come BEFORE effect
A prospective cohort study follows a group of individuals over a period of time to see…
how certain exposures affect later outcomes
What is an odds ratio (OR) in sleep research used for?
To quantify the strength of the association between sleep problems and the subsequent development of mental health diagnoses over time
Why is Odds Ratio (OR) so important?
- Because it considers BOTH groups!
- The OR it tells you how MANY times more likely it is that you would develop a MH diagnosis if you had sleep problems compared to not having sleep problems
In sleep research, what do the following odds ratios (OR) mean?
1. OR = 1
2. OR greater than 1
3. OR less than 1
- Sleep problems do NOT affect the likelihood of developing a mental health diagnosis
- Individuals with sleep problems are MORE likely to develop a mental health diagnosis compared to those without sleep problems
(e.g. OR = 2 meaning that people with sleep problems are 2 x MORE likely to develop a mental health diagnosis over 1 year compared to those without sleep problems) - Individuals with sleep problems are LESS likely to develop a mental health diagnosis compared to those without sleep problems
What is a meta-analysis?
A method of combining and analysing data from many studies that address the same research question
In a forest plot, each study has what two things?
- An effect size (square)
- Confidence interval (line through square)
What is the line of no effect in a forest plot?
This is placed at the point where the effect size equals no effect.
When an Odds ratio is 1, why is the line of no effect at 1?
Because an OR of 1 means that there is no difference in odds between the two groups being compared.
What did Hertenstein et al (20203) meta-analysis of longitudinal studies examine?
Whether insomnia predicts later mental health diagnosis
Insomnia increases the risk of developing what four conditions at a later point in time?
- Depression
- Anxiety
- Alcohol abuse
- Psychotic disorders
(strongest for anxiety and depression)
What was the aim of Koren et al (2002)?
Explore the role of sleep complaints post-trauma in the development of PTSD
Who did Koren et al (2002) study?
102 survivors of motor vehicle accidents followed up over 1 year