PHEBD Flashcards
What is meant by “Dental Public Health”?
The science of practice and preventing oral disease, promoting oral health and improving quality of life through the organised efforts of society
What is meant by “Epidemiology”?
What is meant by _____ Epidemiology?
1) Descriptive
2) Analytical
Epidemiology = tool used to help study the distribution and determinants of health and disease.
This knowledge can then be used to control disease and its spread.
1) DESCRIPTIVE Cross-sectional studies (who/how many people) 2) ANALYTICAL "WHY" people have the disease... Looking at RCTs or Case-control
What is the most common index used to record caries?
What are its advantages (2) and disadvantages (3)?
DMFT = Decayed Missing Filled Teeth
Advantages:
- Well-established index
- Allows data comparison internationally and over time
Disadvantages:
- Limits in interpreting “M” in adults - what was reason for tooth loss?
- Person with 10 decayed teeth has same score as someone with 10 missing teeth
- No information about number of teeth at risk
What are 3 indices to measure caries risk?
1) DMFT
2) ICDAS - International Caries Detection and Assessment System
3) T-Health - Measures number of “sound” teeth
What is meant by external validity?
How representative a study is of the general population and therefore how well the results can be integrated into practice
What are 5 factors that affect external validity?
1) Participants - representative of general population?
2) Setting - representative of setting you would be seeing Px in?
3) Operator - can it be done by general dentist or are specialists used?
4) Outcomes - how are these tested?
5) Duration - longer is best
What is internal validity? What types of studies generally have the highest internal validity and why?
How well the study is run: How much the results represent the variable in question and elimination of any confounding bias.
(This can be done by elimination of bias, double blind trial and randomisation)
RCT have the highest internal validity as they minimise risk of confounding bias
What is meant by “Confounding” Bias/Variables?
Variables affecting the result of the study more than the experimental variable of interest. These alter/”confound” the result, so a high risk of confounding bias → low validity
What is meant by critical appraisal?
The process of carefully and systematically examining research to judge its trustworthiness, value and relevance in a particular context
What are 4 ways in which researchers can improve External Validity?
1) Large sample size - range of people to represent general population
2) Random selection of Px’s
3) Involving various dental practices from different areas of the country (including NHS and Private)
4) Selecting the trial setting to reflect normal Px treatment area (e.g. in GDP)
What is meant by “Bias”?
If a study has bias, does this reduce the internal or external validity?
An inclination/prejudice for or against a certain study outcome, affecting the study results so they no longer reflect a “true” picture.
This affects INTERNAL validity
What are 4 main types of bias?
Briefly explain each
1) SELECTION BIAS
Systematic differences between each group, so no longer representative of general/target population
2) PERFORMANCE BIAS
Trial groups treated differently (e.g. one seen more often)
3) ATTRITION BIAS
Reduction in number of participants in a study over time - to be expected in LT studies but they should investigate whether all ex-participants shared similar traits and ensure groups still represent general population
4) REPORTING BIAS
When only good outcomes are reported (and bad are not)
