Study Designs by Jennifer Fletcher https://padlet.com/jfletcherama/h94d58uavxgd Descriptions, Strengths and Limitations en-us 2017-08-09 01:45:17 UTC 2026-01-08 05:06:22 UTC hello@padlet.com https://padlet-assets.s3.amazonaws.com/icons/Balance.png Case control https://padlet.com/jfletcherama/h94d58uavxgd/wish/180996434 Description 
Patients with certain diseases are compared to a control group without the disease. Looking retrospectively for risk factors

Strengths
- quick and cheap
- good for disorders with long lag time
- only a few subjects needed

Limitations 
- reliance on recall
- cofounders
- finding control groups is hard
- bias: recall, selection]]> 2017-08-14 22:39:48 UTC https://padlet.com/jfletcherama/h94d58uavxgd/wish/180996434 Cross-Sectional Studies https://padlet.com/jfletcherama/h94d58uavxgd/wish/180996448 Description:
This study looks at the relationship between health conditions or diseases and other variables that are found within a certain population at a determined time

Strengths:
- affordable 
- ethical, non-invasive
- simple method

Limitations:
- issue with bias - recall
- does not determine causality, only association
- unequal group sizes can occur]]> 2017-08-14 22:40:03 UTC https://padlet.com/jfletcherama/h94d58uavxgd/wish/180996448 RCT https://padlet.com/jfletcherama/h94d58uavxgd/wish/180996462 Description- participants are allocated to a treatment or control group through randomisation

Strengths- avoid selection bias, unbiased distribution of confounders, blinding, randomisation= statistical analysis

Limitations- expensive, long-term, non-compliance, ethical issues]]> 2017-08-14 22:40:15 UTC https://padlet.com/jfletcherama/h94d58uavxgd/wish/180996462 Cohort Studies https://padlet.com/jfletcherama/h94d58uavxgd/wish/180996501 description 
study is divided into two (some exposed to risk factor and some who have not been) groups and participants are followed up over a period of time 

strengths
- outcomes over time 
- measure number of new cases
- examine multiple exposures/risk factors and effects on health

limitations
- confounders
-  time 
- loss to follow up 
- costs ]]> 2017-08-14 22:40:57 UTC https://padlet.com/jfletcherama/h94d58uavxgd/wish/180996501 Case control https://padlet.com/jfletcherama/h94d58uavxgd/wish/180996741 Description 
A study that compares patients who have a disease or outcome of interest (cases) with patients who do not have the disease or outcome (controls), and looks back retrospectively to compare how frequently the exposure to a risk factor is present in each group to determine the relationship between the risk factor and the disease.

Strengths 
  • Good for studying rare conditions or diseases
  • Less time needed to conduct the study because the condition or disease has already occurred
  • Lets you simultaneously look at multiple risk factors
  • Useful as initial studies to establish an association
  • Can answer questions that could not be answered through other study designs

Limitations 
  • Retrospective studies have more problems with data quality because they rely on memory and people with a condition will be more motivated to recall risk factors (also called recall bias).
  • Not good for evaluating diagnostic tests because it’s already clear that the cases have the condition and the controls do not
  • It can be difficult to find a suitable control group
]]> 2017-08-14 22:44:07 UTC https://padlet.com/jfletcherama/h94d58uavxgd/wish/180996741