Pubh192 (Lectures 4-6)

Taking into account the best available research evidence and patient values and choices. Using clinical expertise.

1.) Expert opinions may be wrong

2.) A trial is the best way to identify effective treatment

3.) Dangerous just to rely on animal studies, observational studies and trials of surrogate outcomes

4.) Do not allow current opinion, bias and enthusiasm for treatment cloud judgement

5.) Be careful in deciding if causal relationship

6.) Require evidence from well designed, conducted and reported randomised controlled trials

Possible determinant of health

Health status

A group of people with similar a similar characteristic

It involves describing patterns of health and disease, the impact of disease and trends across time.

Prevalence, cumulative incidence and incidence rate

The proportion of people in a population who have the exposure/outcome at a particular point in time. "Snapshot"

P= number of existing cases / total population at risk

....at time t (MUST GIVE TIME)

The prevalence of the exposure/outcome in the population at time point/event was value.

Prevalence is influenced by the duration of the disease, doesnt look at causes

The occurrence of new cases of an outcome in the population during a specific period of follow up

The proportion of an outcome-free population that develops the outcome of interest in a specified time period

CI= new cases during time period/population at risk in the beginning

The cumulative incidence of outcome in the population during the time period was value.

1.) Assumes closed population (no one leaving or entering)

2.) Highly dependent on the time period - the longer the time, the higher the incidence (numerator) while the same population (denominator)

The rate at which new cases of the outcome of interest occur in a population (average speed of new cases)

When they are lost to follow up, develop the disease/become a case, are not able to develop the disease (ie: women and prostate cancer) or the follow up time ends

IR = number of new cases during the time period/ total person time at risk of becoming a case

The incidence rate of outcome in the population was value cases per value person years/months/days etc

Dont need time period as already included in rate, also often have to simplify eg: 0.5 cases per 1 person-year or 50 cases per 100 person-years

1.) can get very complicate to calculate

2.) Person-time is often not available

1.) Not dependent on disease duration

2.) Measuring development of disease rather than those that have disease

It is a method to make 2 groups have the same age distribution. This allows measures of occurrence to be compared between different populations. It removes age as a confounder and is important as most diseases are age related.

It is used when you want to compare measures of occurrence between 2 populations but the age structures are different and disease risk varies with age.

Dental carries (decay), periodontal (gum) disease, malocclusion (crooked teeth), tooth loss, enamel defects, mucosal lesions, dry mouth

General = commonly make 1 observation per person

Dental = make many observations per person

Common, age related, chronic, progressive and irreversible.

International, generational, age, area, income, ethnicity, education, disability

Filling vs cavity, composite vs amalgam, extraction vs root canal, implant vs denture, gold vs ceramic crown, budget vs boutique, publicly funded vs private, emergency vs routine, preventative vs interventive

Over generations, average oral health status decreases. The older the person, the more likely they are to have decayed, missing or filled teeth

Maori almost 2x more likely to have missing teeth than non-Maori

People with intellectual disabilities are more likely to have poor oral health and untreated oral diseases

Inequality in the way treatment is provided is far greater than the inequality of the disease itself.

Dentistry has become more hightech with many technological advances. This often means its more expensive. Innovation has led to an increase in inequitable provision of dental care. Treatments are often limited by financial status of patients. Dentists are run like businesses

Upstream= preventative, focuses on determinants of health, can reduce inequality, adresses source problem

Downstream = treatments, rely on changing behaviours, tends to increase inequalities

Upstream = removing taxes on dental products, legislating sugar additives, limit advertising certain risk products, water fluoridation, education initiatives

Downstream = telling a person to brush their teeth, see a dentist, cut back on sugar

Equity of access means access proportionate to need, not necessarily equal for everyone as equality suggests.

Cross sectional - scoping extent of health issue, monitoring populations

Case controlled - investigating risk factors

Cohort - investigating process/disease development, risk factors

1.) Assessing the health status of a population

2.) Comparing impact of a condition among different populations

3.) Planning health services, gives indicators for further investiagtions