1) Audits and Service Evaluations of Healthcare Standards & Guidelines

Question 1

Define a clinical audit

Answer 1

A quality improvement process that seeks to improve patient care and outcomes through systematic review of care against explicit criteria and the implementation of change.

Aspects of the structure, processes, and outcomes of care are selected and systematically evaluated against explicit criteria.

Where indicated, changes are implemented and further monitoring is used to confirm improvement in healthcare delivery.

Question 2

What is the purpose of a clinical audit?

Answer 2

A way to find out if healthcare is being provided in line with standards and lets care providers and patients know where their service is doing well, and where there could be improvements.

Question 3

What does a clinical audit measure existing practices against?

Answer 3

Evidence-based clinical standards (i.e. is what ought to be happening actually happening)

Question 4

What is the ‘hierarchy of evidence’?

Answer 4

A heuristic used to rank the relative strength of results obtained from scientific research.

Question 5

Define heuristic

Answer 5

A heuristic technique, is any approach to problem solving that employs a practical method that is not guaranteed to be optimal, perfect, or rational, but is nevertheless sufficient for reaching an immediate, short-term goal or approximation.

Heuristics can be mental shortcuts that ease the cognitive load of making a decision. Examples that employ heuristics include using trial and error, a rule of thumb or an educated guess. Heuristics are the strategies derived from previous experiences with similar problems.

Question 6

What is one downfall of the hierarchy of evidence?

Answer 6

It focuses exclusively on effectiveness and rarely pays attention to the quality of the studies.

Question 7

Define a ‘case control’ study

Answer 7

A study that selects participants on the basis of their outcome and works back to their exposure

e.g. patients who have developed a disease are identified and their past exposure to suspected aetiological factors is compared with that of controls or referents who do not have the disease

Question 8

Give one advantage and disadvantage of a case control study

Answer 8

Adv - cheap

Disadv - subject to bias

Question 9

What type of bias are case control studies typically prone to? Why?

Answer 9

Selection bias - occurs if the recruited cases or controls are systematically different from the population of people they are intended to represent.

N.B. Case-control studies done in a clinical setting are even further prone to bias because the factors that bring patients to the clinical setting are often related to the disease or risk factor of interest.

Question 10

Within general practice in the UK, recurrent sore throat has an incidence of 100 per 1,000 of the population. In this context a GP is likely to use pattern recognition as a means of reaching a clinical decision.

Which aspect of the pattern recognition model makes this the most appropriate diagnostic method?

1. Requires more conscious effort
2. Based on explicit rules
3. Use of heuristics
4. Slow and deliberate

Answer 10

Use of heuristics

Question 11

What is the pattern recognition model?

Answer 11

Recognising patterns is the process of classifying the data based on the model that is created by training data, which then detects patterns and characteristics from the patterns.

Question 12

What is the exposure distribution?

Answer 12

The proportion having the exposure in the population from which the cases arose

Question 13

What is an odds ratio (OR)?

Answer 13

A measure of the association between exposure and outcome.

The OR represents the odds that an outcome will occur given a particular exposure, compared to the odds of the outcome occurring in the absence of the exposure.

Question 14

How is an OR calculated?

Answer 14

The exposure distribution in cases is compared to the exposure distribution in the controls in order to compute the odds ratio as a measure of association.

Question 15

What does an OR < 1 indicate?

Answer 15

Indicates decreased occurrence of an event (protective exposure).

Question 16

What does an OR > 1 indicate?

Answer 16

Indicates increased occurrence of an event

Question 17

A study examines the relationship between oestrogen (exposure) and endometrial cancer (outcome).

Calculate the odds ratio

Answer 17

Odds of cancer in those exposed to oestrogen → a/c = 56/18

Odds of cancer in those not exposed to oestrogen → b/d = 274/390

Calculate odds ratio by dividing first group by second group.

(56/18) / (274/390) = 4.42

Individuals with endometrial cancer are 4.42 times more likely to be exposed to oestrogen than those with endometrial cancer.

NOTE it is not appropriate to interpret this as ‘individuals with oestrogen exposure are 4.42x more likely to develop endometrial cancer’. This is because a case-control study begins from the outcome (i.e. selection of a sample with the outcome).

Question 18

What does an OR = 1 indicate?

Answer 18

Means that exposure to A does not affect the odds of B.

Question 19

What is selection bias?

Answer 19

In a case control study, selection bias occurs when subjects for the ‘control’ group are not truly representative of the population that produced the cases → non-comparability between cases and controls.

Question 20

Why is selection bias a particular problem where cases and controls are recruited exclusively from hospital/clinics?

Answer 20

Hospital patients tend to have different characteristics than the population e.g. higher levels of alcohol/smoking

Question 21

How can selection bias be avoided?

Answer 21

Randomisation

Question 22

What is a cohort study?

Answer 22

Longitudinal study; an exposure is assessed (common characteristic) and then participants are followed prospectively to observe whether they develop the outcome e.g. potential long-term consequences of the use of oral contraceptives

Question 23

Define prospective

Answer 23

studies are planned in advance and carried out over a future period of time

Question 24

Define retrospective

Answer 24

studies look at data that already exists and try to identify risk factors for particular conditions

Question 25

What is a randomised controlled trial?

Answer 25

A number of similar people are randomly assigned to 2 (or more) groups to treatment groups (e.g. drug)

• One group has the intervention being tested (the experimental group)
• The other has an alternative intervention (placebo) or no intervention at all (the control group)
• The groups are followed up to see how effective the experimental intervention was

Question 26

Purpose of a randomised controlled trial?

Answer 26

Used to control factors not under direct experimental control.

Question 27

Advantages & disadvantages of a randomised controlled trial?

Answer 27

• ADVS: Participants selected before outcome and exposure controlled
• DISADVS: Expensive

Question 28

What is meta-analysis?

Answer 28

A method often used in systematic reviews to combine results from several studies of the same test, treatment or other intervention to estimate the overall effect of the treatment (a formal study of existing evidence)

Question 29

What is a service evaluation?

Answer 29

Evaluates a current service or proposed practice to assess how well a service is achieving its intended aims:

• What does the existing service entail?
• Can this be improved?
• What do practitioners think of a proposed new service?

Question 30

Purpose of a service evaluation?

Answer 30

Undertaken to benefit the people using a particular healthcare service and designed and conducted with the sole purpose of defining or judging the current service

Question 31

Clinical audit vs a service evaluation?

Answer 31

A clinical audit is designed to answer the question → ‘Does this service reach a certain standard?’

A service evaluation is designed to answer the question → ‘What standard does/might this service achieve?’

Question 32

What is an audit-cum-service evaluation?

Answer 32

Many studies conduct both an audit (to establish the extent to which clinical practice is achieving a particular standard) as well as a service evaluation (to establish what factors might be associated with those contexts)

Question 33

Example of an audit-cum-service evaluation:

EXAMPLE: Following a stroke, patients may experience dysphagia. NICE guidelines recommend swallowing therapy “at least three times a week for as long as they continue to make functional gains”

Answer 33

• Study 1 AUDIT: What proportion of patients with dysphagia are given swallowing therapy at least 3 times a week?
• Study 2 SERVICE EVALUATION: How many times a week are patients given swallowing therapy?
• Study 3 AUDIT-CUM-SERVICE EVALUATION: What proportion of patients with dysphagia are given swallowing therapy at least 3 times a week in Consultant-led and non-Consultant-led clinics?
• Study 4 RESARCH: How might early aspirin administration influence the need for swallowing therapy?

Question 34

What axis is the exposure on?

Answer 34

x

Question 35

What axis is the outcome on?

Answer 35

y