RESS revision Flashcards
1
Q
4 steps in clinical audit cycle
A
1 = preparation and planning 2 = measuring performance 3 = implementing change 4 = sustaining improvement (including re-audit)
2
Q
what does a service evaluation do
A
evaluates current service/proposed practice - intention of generating info to inform local decision-making
3
Q
research cycle 8 steps
A
- identifying topics
- commissioning
- designing research
- managing research
- data collection
- analysis and interpretation
- dissemination
- evaluation
4
Q
is NICE non governmental
A
yes
5
Q
who funds NICE
A
department of health
6
Q
who appoints board and chair of NICE
A
secretary of state
7
Q
8 of NICE’s core principles
A
scientific rigour inclusiveness transparency independence challenge review support for implementation timeliness
8
Q
what are NICE quality standards (not the same as NICE guidelines)
A
prioritised, concise set of statements (6-8) with associated measurable indicators, chosen and adapted from clinical guideline recommendation s
9
Q
what do NICE guideline and development groups (GDGs) do
A
review and make judgements based on evidence and make recommendations - respond to consultation comments
10
Q
what do NICE national collaborating centres (NCCs) do
A
convene GDGs, provide technical input to facilitate GDG, draft guidlines
11
Q
4 things making up a GDG
A
chair (clinical leader)
clinical and academic experts
patients, carers, lay members
NCC technical team
equal status
12
Q
what happens if an exposure occurs after an outcome
A
it is a consequence of it (descendant)
13
Q
what are covariates
A
variables that might cause either the exposure and/or outcome
14
Q
3 types of covariates
A
confounder
mediator
competing exposure
15
Q
what does a confounder cause
A
both outcome and exposure
16
Q
what does a mediator cause
A
outcome, and caused by exposure
17
Q
what does a competing exposure cause
A
outcome only
18
Q
why do we adjust for confounders
A
create a pseudo-causal path between outcome and exposure = generates statistical relationship between them even when none exists
19
Q
why do we NOT adjust for mediators
A
part of the causal path between outcome and exposure - risk ‘adjusting out’ this pathway
20
Q
why MIGHT we adjust for competing exposures
A
may cause a substantial amount of the variation in the exposure
21
Q
4 types of variable which are necessary
A
exposure
outcome
measurable/available confounders
measurable/available competing exposures
22
Q
are mediators necessary variables
A
no
23
Q
example of a prospective study
A
cohort - measure/record variables during the study period with the outcome subsequently measured
24
Q
example of a retrospective study
A
case-control - record/measure outcome then look back to find exposure and covariates
25
are cross-sectional studies prospective or retrospective
both
26
what is a latent variable
missing variable
27
what is target population
total finite population of those we wish to apply study results and from which any study sample is drawn
28
what is study sample
people/contexts from WITHIN the target population selected for analysis
29
what is complete sample
entire study population
30
what is unstratified random/probability sample
every member of target population has same chance of being sampled
31
what is stratified random/probability sample
randomly sample from target population within strata
32
what is quota sampling
sample taken from stratified population until pre-assigned quota in each stratum is represented
33
is quota sampling random
NO
34
what is cluster sampling
when 'natural' but homogenous groupings are evident in population e.g. regions of the UK - simple random sampling used within each cluster
35
what is the odds ratio if there is NO EFFECT
1
36
how to use confidence interval and OR to see if effect is genuine
if 95% Cl round the OR does NOT include 1 = genuine
37
how to improve OR confidence interval
increase sample size - OR stays same but CI increases to above 1
38
what STATA command is used to build linear models/regressions
regress command
39
how to use STATA regress command if data is categorical
use same regress command but precede 'regress' with 'xi' then indicate which variables are categorical by putting 'i' in front of their name
e.g. xi: regress weight i.sex
40
2 types of categorical data
nominal (names etc)
ordinal (scale)
no numerical value
41
how to make ordinal data numerical
rank scale to each category - but will still be classed as categorical
42
type of analysis for continuous outcome data
multivariable linear regression analyses
43
type of analysis for binary outcome data
multivariable logistics regression analyses
44
what is model misspecification
incorrectly specified multivariable regression model in terms of:
- non linear relationships
- omitting important variables e.g. confounding bias
- overadjustment
- transformation of variables e.g. categorising continuous data
45
when does heterogeneity bias (group difference bias) occur
natural group structures in data and there are differences in the groups that are correlated with the study variable
46
how many authors used before 'et al'
6/7
47
what is the Likert scale (example of ordinal data)
strongly disagree, disagree ... strongly agree
48
what type of data is age
numerical continuous - but often grouped as discrete
49
what is relative frequency
percentage of total frequency accounted for by particular variables
50
how to calculate incidence rate
number of new cases occurring in set time / number of people at risk in set time
51
epidemiological triad
time
person
place
52
how to calculate mortality rate
number of people who die from disease in period / number of people who die in period of all causes
53
how to calculate case fatality
number of people who die from a disease in period / number of people with the disease
54
how to calculate OR
odds for disease of exposed group / odds of disease of unexposed group
55
when can ORs be used in RCTs
when the RCT is dichotomous
56
what are dichotomous variables
variable takes 1 of 2 forms that are completely different e.g. dead or alive
57
type of data for histograms
numerical continuous
58
measure of distribution in non-normally distributed data
median and IQR (so isnt affected by outliers)
59
what is standard error a measure of
precision - how reliable the sample population mean is from that of the population
60
when is correlation the appropriate statistical analysis
when both the outcome and exposure are numerical
61
appropriate statistical analysis for if the outcome is numerical and the exposure is categorical (independent groups)
T test or Mann-Whitney test
62
what is an inductive hypothesis
hypothesis proposed after analysis - explains why two sets of info are related to one another
63
what is a deductive hypothesis
proposed before analysis - think that at least 2 variables are related
64
what does adding an asterisk to the end of a word mean when refining a search
truncated ending where alternative ending would be accepted
65
what are boolean operators
to refine searches e.g. AND, OR, NOT
66
what type of study is a census
cross-sectional - looks at entire population at defined time assessing prevalence
67
what is Ansecomb's quartet
4 sets of data with same statistical properties which look very different when displayed graphically
68
what is responsiveness
whether a measure can detect real change (over time)
69
what is type 1 error
incorrect rejection of a true NULL hypothesis (false positive for alternative)
70
what is type 2 error
failure to reject a false null hypothesis (false negative for alternative)
71
what is chi squared used for
determine association between categorical variables
72
how is standard error calculated
standard deviation / square root of sample size
73
what is interval sampling
taking samples at set intervals e.g. drugs company take a sample of every 100th drug etc
74
what phase of a clinical trial assesses effectiveness and dosages of drugs on a few hundred patients WITH the disease?
phase II
75
what is a systematic review
mini reports that are peer reviewed - focus on specific topic
76
what is a consensus study
consensus statement developed by professionals via a group consensus process that is intended to advance health professional and/or public understanding of a targeted health problem
77
how to calculate risk
risk = number of new cases / number at risk
78
in what type of study do you use a risk ratio
cohort - used to find risk factors (exposures) of disease
79
what type of study to use OR
case-control study or RCT
80
what is relative risk reduction
RRR = 100-RR - i.e. the difference the new treatment makes to the condition (compared to old/untreated group)
81
range of values of risk
0-1
82
correlation coefficient used for normally distributed data
Pearson correlation coefficient (r) -1 to 1
83
correlation coefficient used for not normally distributed data, when 1 or both of the variables are ordinal, or when the sample size is small
Spearman's
84
do larger or smaller studies have a larger confidence interval
smaller studies = large CI
85
what is opportunity cost
value of something when a particular course of action is chosen - what you must forgo in order to get something
benefit foregone from not using the same resources in the next best activity
86
when have you made the wrong choice in opportunity cost
if it is greater than the value of what you choose - should aim to minimise the opportunity cost of choices
87
what is economic evaluation
comparison of 2+ alternative courses of action in terms of their costs and their outcomes
88
2 types of efficiency
technical efficiency
| allocative efficiency
89
what is technical efficiency
meeting a given objective at least cost
90
what is allocative efficiency
producing the output (supply) that matches consumer want (demand) - is an activity worthwhile?
91
2 things marginal analysis involves
comparing:
- the benefit from that next step (Marginal Benefit) with
- the cost of taking the next step (Marginal Cost)
NOT interested in average cost and benefit
92
type of cost analysis when we want to compare alternatives WITHIN a condition
cost effectiveness analysis - benefits measured in terms of standard clinical outcome e.g. change in blood pressure
93
3 types of cost analysis when we want to compare ACROSS conditions
- cost effectiveness analysis (also considers life years gained)
- cost utility analysis (considers both quality and quantity of life)
- cost benefit analysis (considers resource use and health benefits in monetary terms)
94
what is the Incremental Cost Effectiveness Ratio (ICER)
expected cost per additional unit of health produced by a new intervention compared to current practice
95
what is the cost effectiveness threshold
maximum amount the health service will pay per unit of health gained - represents maximum opportunity cost consistent with improving population by introducing a new intervention
96
NICE threshold for cost effectiveness per QALY gained
£20-30k
97
what is option appraisal
process for identifying, describing and evaluating alternative methods (options) of achieving an agreed objective
98
hierarchy of evidence top to bottom
```
meta-analysis
systematic review
critically appraised topic
RCTs
cohort studies
case-controlled studies/case series/reports
background info/expert opinion
```
99
what is a case control study
select participants on basis of their outcome and works back to exposure = cheap, bias
100
what is a cohort study
longitudinal study following group of people over time, selects participants before the outcome but no control over exposure
101
what does a service evaluation do
evaluates a current service/proposed practice
102
difference between audit and service evaluation
audit = does it reach a standard (practice against target)
| service evaluation = what standard does/might this achieve (current practice)
103
what does an audit-cum-service evaluation examine
whether variation in practice may cause variation in compliance - variation in compliance may cause variation in benefit?
104
what is response bias
what interview wants/gets
105
what is prestige bias
what appears favourable
106
what is over adjustment bias
controlling for an intermediate variable or mediator in multivariable regression analysis
107
what is multicollinearity
when there are strong associations or correlations among covariates in a multivariable regression model
108
what is pharmacodynamics
what the drug does to the body
109
what is pharmacokinetics
what the body does to the drug
110
what does ADME stand for
absorption
distribution
metabolism
elimination
for pharmacokinetics
