research quiz 3

prognosis research question

what is the relationship between an exposure/risk factor and an outcome

types of prognosis studies

cohort and case control

characteristics of prognosis research design

quantitative, nonexperimental, within or between subjects, cross-sectional or longitudinal, retro or prospective

uses of prognostic studies

predicting a future condition, surveillance/preventative techniques, informs differential diagnosis and treatment planning, predicts functional outcomes

what can be seen about a prognosis in a cross-sectional study

prevalence (how many people have it at a given time)

what can be seen about a prognosis in a longitudinal study

development and inheritance

what is included in a prognosis

ultimate outcomes of a health condition, results of pt interventions

elements of prognosis study designs

large group, observed over time (cohort studies)

elements of the exposure in a prognosis study

the independent variable, predictors, comparison of incidence in people who were exposed and who were not (strength of relationship of factor and outcome)

elements of the outcome in a prognosis study

development of disease, presence of disease, must be preceded by an exposure

incidence rate

number of new cases within a period

measure of incidence

person-years

prevalence

proportion of cases in the population at a given time

measure of prevalence

number of cases/total number studied (percent)

relative risk measure

quantifies the strength of association of exposure with the outcome compared to a reference group

parts of a relative risk measure

risk ratio and odds ratio

relative values when the exposed has less risk of an outcome

small: 0.8, moderate: 0.8-0.3, large: 0.2

relative values when the exposed has more risk of an outcome

small: 2, moderate: 3-5, large: 5

risk ratio

incidence in the exposed/incidence in the unexposed

odds ratio

odds of exposure among diseased vs non diseased

disadvantage of relative risk measures

cannot tell the absolute amount, always relative because a ratio expresses probability and comparisons

absolute measures of risk

absolute risk difference, number needed to treat/harm

definition of clinical practice guidelines

systematically developed statements that include recommendations to assist practitioner and pt decisions and optimize pt care

parts of CPGs

systematic review and clinical recommendations

pros of CPGs

grades evidence succinctly, reduces variation in practice, decreases knowledge translation gap, allows for complete evidence based practice

focus of CPGs in PT

diagnostic tests, clinical predictions, prognostic indicators, outcome measures, patient management

steps of developing CPGs

identify topic and scope → form creation team → systematic review → develop recommendations → determine limitations of the evidence

levels of evidence in CPGs

high (RCT and systematic reviews), lesser quality (cohort studies), case control and case series, expert opinion

P grading

best practice

R grading

research

A levels of evidence

1 and 2 (high quality)

B levels of evidence

2

limitations of CPGs

depends on levels of evidence, vulnerable to bias, age

decisions to consider when implementing a CPG

relevance to the pt, time, resources, practice environment, was it worth it

problems of a single clinical trial

small sample size, single geographic location, specific inclusion/exclusion criteria, may not be reproducible/generalizable

PRISMA guidelines

evidence based minimum set of items for reporting in systematic reviews and meta analyses

pros of systematic reviews

lots of evidence with exponential increase in RCTs, address limitations of a single study, provides a summary of the evidence, identifies gaps in understanding

meta analysis

quantitative form of systematic review which data is pooled to draw conclusions

forest plot

visual summary of the effect estimates (summarizes results)