Professional Practice and Ethics: Scope, Counselling, Evidence and Regulation
Professional practice items test judgement as much as knowledge: whether you stay inside your scope, obtain consent, protect confidentiality, counsel effectively, and read a study without overstating it. Evidence-appraisal calculations appear regularly, especially NNT and predictive values.
Scope and ethics
Practise within your legal scope and competence, and refer when a case exceeds either. The four principles are autonomy (respect the patient's informed choice), beneficence, non-maleficence and justice (fair allocation of resources). Obtain informed consent for assessment and intervention, explain alternatives and limits, keep records confidential, disclose conflicts of interest including industry sponsorship, and avoid unsupported claims for supplements or tests.
Communication and counselling
Motivational interviewing uses OARS: open questions, affirmations, reflections and summaries. Roll with resistance rather than confronting it, elicit the patient's own reasons for change, and match advice to the stage of change. Confirm understanding with teach-back, adjust for health literacy, and use interpreters or simple written plans when language or numeracy is limited. Document goals in behavioural, measurable terms.
Evidence appraisal
- Hierarchy: systematic reviews and meta-analyses of randomised trials, then individual randomised controlled trials, cohort studies, case-control studies, cross-sectional surveys, case reports and expert opinion.
- Internal validity depends on randomisation and allocation concealment, blinding, intention-to-treat analysis, handling of loss to follow-up, and control of confounding.
- Report both relative and absolute effects: absolute risk reduction, relative risk, odds ratio, hazard ratio, and 95% confidence intervals. NNT = 1 / absolute risk reduction.
Diagnostic numbers
Sensitivity = TP / (TP + FN); specificity = TN / (TN + FP); predictive values depend on prevalence, so a good test in a high-risk group performs poorly when applied to everyone.
Worked example
A trial reports events in 20% of controls and 14% of the intervention group: absolute risk reduction = 6%, so NNT = 1 / 0.06 = about 17 patients treated to prevent one event, even though the headline relative reduction is a more impressive 30%. Separately, a test with 90% sensitivity and 95% specificity in a population with 1% prevalence: of 10 000 people, 100 have the condition and 90 are detected, while 495 of the 9900 healthy people are false positives. Positive predictive value = 90 / 585 = only about 15%.
Traps that cost marks
Quoting relative risk reduction as if it were absolute benefit. Treating sensitivity as fixed once prevalence changes. Ignoring intention-to-treat results and accepting per-protocol analysis. Placing expert opinion above systematic reviews. Giving advice outside scope, or recommending a supplement whose evidence base is a single small uncontrolled study.