-
Question 1
Correct
-
Which of the following drugs used in the management of hyperkalaemia does not affect serum potassium levels:
Your Answer: Calcium gluconate
Explanation:Calcium gluconate is given to antagonise cardiac cell membrane excitability to reduce the risk of arrhythmias. It has no effect on serum potassium levels unlike the alternative drugs listed above.
-
This question is part of the following fields:
- Fluids And Electrolytes
- Pharmacology
-
-
Question 2
Incorrect
-
A 63-year-old man complains of chest pain and syncope on occasion. His heart rate is 37 beats per minute, and he has a second-degree heart block, according to his rhythm strip.
Which of the following would be the most appropriate next step in his management, according to the ALS bradycardia algorithm?Your Answer: Give glucagon 1 mg
Correct Answer: Give atropine 500 mcg
Explanation:Atropine is used to treat bradycardia (sinus, atrial, or nodal) or AV block when the patient’s haemodynamic condition is compromised by the bradycardia.
If any of the following adverse features are present, the ALS bradycardia algorithm recommends a dose of atropine 500 mcg IV:
Shock
Syncope
Myocardial ischemia
Insufficiency of the heartIf this does not work, give additional 500 mcg doses at 3-5 minute intervals until a maximum dose of 3 mg is reached. The heart rate can be slowed paradoxically if the dose is higher than 3 mg.
The ALS bradycardia algorithm also suggests the following interim measures:
Transcutaneous pacing
Isoprenaline infusion 5 mcg/min
Adrenaline infusion 2-10 mcg/minutes
Alternative drugs (aminophylline, dopamine, glucagon, glycopyrrolate) -
This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
-
-
Question 3
Incorrect
-
Which of the following is an adverse effect of carbamazepine:
Your Answer:
Correct Answer: Aplastic anaemia
Explanation:Common adverse effects include nausea and vomiting, sedation, dizziness, headache, blurred vision and ataxia. These adverse effects are dose related and are most common at the start of treatment.
Other adverse effects include:
Allergic skin reactions (and rarely, more serious dermatological conditions)
Hyponatraemia (avoid concomitant use with diuretics)
Leucopenia, thrombocytopenia and other blood disorders including aplastic anaemia
Hepatic impairment -
This question is part of the following fields:
- Central Nervous System
- Pharmacology
-
-
Question 4
Incorrect
-
Regarding bronchiolitis, which of the following statements is CORRECT:
Your Answer:
Correct Answer: Chest x-ray may show hyperinflation and increased peribronchial markings.
Explanation:Acute bronchiolitis is caused most commonly by respiratory syncytial virus, occurring mostly in children aged 6 months to 2 years. Children with bronchiolitis are febrile and tachypnoeic with a dry cough and difficulty feeding. Examination may reveal chest hyperinflation, respiratory distress, wheezing and fine end-inspiratory crepitations. Chest x-ray may show hyperinflation and increased peribronchial markings (although CXR should only performed if there is diagnostic uncertainty or an atypical course). Treatment is usually supportive, aerosolized ribavirin is reserved for severely ill or immunocompromised patients.
-
This question is part of the following fields:
- Microbiology
- Pathogens
-
-
Question 5
Incorrect
-
On her most recent blood tests, a 55 year-old female with a history of hypertension was discovered to be hypokalaemic. She is diagnosed with primary hyperaldosteronism.
Which of the following is a direct action of aldosterone?
Your Answer:
Correct Answer: Secretion of H + into the distal convoluted tubule
Explanation:Aldosterone is a steroid hormone produced in the adrenal cortex’s zona glomerulosa. It is the most important mineralocorticoid hormone in the control of blood pressure. It does so primarily by promoting the synthesis of Na+/K+ATPases and the insertion of more Na+/K+ATPases into the basolateral membrane of the nephron’s distal tubules and collecting ducts, as well as stimulating apical sodium and potassium channel activity, resulting in increased sodium reabsorption and potassium secretion. This results in sodium conservation, potassium secretion, water retention, and a rise in blood volume and blood pressure.
Aldosterone is produced in response to the following stimuli:
Angiotensin II levels have risen.
Potassium levels have increased.
ACTH levels have risen.
Aldosterone’s principal actions are as follows:
Na+ reabsorption from the convoluted tubule’s distal end
Water resorption from the distal convoluted tubule (followed by Na+)
Cl is reabsorbed from the distal convoluted tubule.
K+ secretion into the convoluted distal tubule’s
H+ secretion into the convoluted distal tubule’s -
This question is part of the following fields:
- Physiology
- Renal Physiology
-
-
Question 6
Incorrect
-
A 20-year-old female presents with painful wrist following a fall while skating. X-rays shows fracture of the ulna.
The initial phase of bone healing is?
Your Answer:
Correct Answer: Haematoma at the fracture site
Explanation:Haemorrhage occurs into the fracture site from the ruptured vessels in the bone marrow and those supplying the periosteum immediately after fracture. This hematoma formation is the first phase of bone healing.
The 4 stages of bone healing are:
Haematoma at the fracture site (provides a framework for healing)
Callus formation
Lamellar bone formation
Remodelling -
This question is part of the following fields:
- General Pathology
- Pathology
-
-
Question 7
Incorrect
-
As a result of a cardiovascular drug she was prescribed, a 67-year-old woman develops corneal microdeposits.
Which of the following drugs is the MOST LIKELY cause?Your Answer:
Correct Answer: Amiodarone
Explanation:Corneal microdeposits are almost universally present (over 90%) in people who have been taking amiodarone for more than six months, especially at doses above 400 mg/day. Although these deposits usually cause no symptoms, about 10% of patients report seeing a ‘bluish halo.’ This goes away once the treatment is stopped, and it rarely causes vision problems.
Other effects of amiodarone on the eye are much rarer, occurring in only 1-2 percent of patients:
Optic neuropathy is a condition that affects the eyes.
Non-arteritic anterior ischaemic optic neuropathy (N-AION)
Swelling of the optic disc -
This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
-
-
Question 8
Incorrect
-
Which of the following is most likely to cause a bitemporal hemianopia:
Your Answer:
Correct Answer: Pituitary adenoma
Explanation:A bitemporal hemianopia is most likely due to compression at the optic chiasm. This may be caused by pituitary tumour, craniopharyngioma, meningioma, optic glioma or aneurysm of the internal carotid artery. A posterior cerebral stroke will most likely result in a contralateral homonymous hemianopia with macular sparing.
-
This question is part of the following fields:
- Anatomy
- Central Nervous System
-
-
Question 9
Incorrect
-
You examine a patient who is experiencing a worsening of his chronic heart failure. You discuss his care with the on-call cardiology registrar, who recommends switching him from furosemide to bumetanide at an equivalent dose. He's on 80 mg of furosemide once a day right now.
What is the recommended dose of bumetanide?Your Answer:
Correct Answer: 2 mg
Explanation:Bumetanide is 40 times more powerful than furosemide, and one milligram is roughly equivalent to 40 milligrams of furosemide. This patient is currently taking 80 mg of furosemide and should be switched to a 2 mg bumetanide once daily.
-
This question is part of the following fields:
- Cardiovascular Pharmacology
- Pharmacology
-
-
Question 10
Incorrect
-
A lung function test is being performed on a male patient. For this patient, which of the following volumes for functional residual capacity is considered a normal result?
Your Answer:
Correct Answer: 2.0 L
Explanation:The volume of air that remains in the lungs after a single breath is known as functional residual capacity (FRC). It is calculated by combining the expiratory reserve volume and residual volume. In a 70 kg, average-sized male, a normal functional residual capacity is approximately 2100 mL.
-
This question is part of the following fields:
- Physiology
- Respiratory Physiology
-
-
Question 11
Incorrect
-
Which of the following describes the site of a Meckel's diverticulum:
Your Answer:
Correct Answer: Ileum
Explanation:Meckel’s lies on the antimesenteric surface of the middle-to-distal ileum, approximately 2 feet proximal to the ileocaecal junction. It appears as a blind-ended tubular outpouching of bowel, about 2 inches long, occurring in about 2% of the population, and may contain two types of ectopic tissue (gastric and pancreatic). The rich blood supply to the diverticulum is provided by the superior mesenteric artery.Proximal to the major duodenal papilla the duodenum is supplied by the gastroduodenal artery (branch of the coeliac trunk) and distal to the major duodenal papilla it is supplied by the inferior pancreaticoduodenal artery (branch of superior mesenteric artery). The arterial supply to the jejunoileum is from the superior mesenteric artery.
-
This question is part of the following fields:
- Abdomen
- Anatomy
-
-
Question 12
Incorrect
-
Which of the following corticosteroids has the most potent mineralocorticoid effect:
Your Answer:
Correct Answer: Fludrocortisone
Explanation:Fludrocortisone has the most potent mineralocorticosteroid activity, making it ideal for mineralocorticoid replacement in adrenal insufficiency.
-
This question is part of the following fields:
- Endocrine
- Pharmacology
-
-
Question 13
Incorrect
-
Regarding loop diuretics, which of the following statements is INCORRECT:
Your Answer:
Correct Answer: The risk of hypokalaemia is greater with loop diuretics than with an equipotent dose of a thiazide diuretic.
Explanation:Hypokalaemia can occur with both thiazide and loop diuretics. The risk of hypokalaemia depends on the duration of action as well as the potency and is thus greater with thiazides than with an equipotent dose of a loop diuretic. Hypokalaemia is dangerous in severe cardiovascular disease and in patients also being treated with cardiac glycosides. Often the use of potassium-sparing diuretics avoids the need to take potassium supplements. In hepatic failure, hypokalaemia caused by diuretics can precipitate encephalopathy, particularly in alcoholic cirrhosis.
-
This question is part of the following fields:
- Cardiovascular
- Pharmacology
-
-
Question 14
Incorrect
-
A patient suffers a stab wound to the neck. The entry point of the blade is situated within the anterior triangle of the neck.
Which of the following muscles is most likely to be involved? Select ONE answer only.Your Answer:
Correct Answer: Sternothyroid
Explanation:The anterior triangle is the triangular area of the neck found anteriorly to the sternocleidomastoid muscle. It is formed by the anterior border of sternocleidomastoid laterally, the median line of the neck medially and by the inferior border of the mandible superiorly. The apex of the anterior triangle extends towards the manubrium sterni. The anterior triangle contains:
Muscles: thyrohyoid, sternothyroid, sternohyoid muscles
Organs: thyroid gland, parathyroid glands, larynx, trachea, esophagus, submandibular gland, caudal part of the parotid gland
Arteries: superior and inferior thyroid, common carotid, external carotid, internal carotid artery (and sinus), facial, submental, lingual arteries
Veins: anterior jugular veins, internal jugular, common facial, lingual, superior thyroid, middle thyroid veins, facial vein, submental vein, lingual veins
Nerves: vagus nerve (CN X), hypoglossal nerve (CN XII), part of sympathetic trunk, mylohyoid nerveThe posterior triangle is a triangular area found posteriorly to the sternocleidomastoid muscle. It has three borders; anterior, posterior and inferior borders. The anterior border is the posterior margin of the sternocleidomastoid muscle. The posterior border is the anterior margin of the trapezius muscle, while the inferior border is the middle one-third of the clavicle. The investing layer of deep cervical fascia and integument forms the roof of the space, while the floor is covered with the prevertebral fascia along with levator scapulae, splenius capitis and the scalene muscles. The inferior belly of omohyoid subdivides the posterior triangle into a small supraclavicular, and a large occipital, triangle.
Contents:
Vessels: the third part of the subclavian artery, suprascapular and transverse cervical branches of the thyrocervical trunk, external jugular vein, lymph nodes
Nerves: accessory nerve (CN XI), the trunks of the brachial plexus, fibers of the cervical plexus -
This question is part of the following fields:
- Anatomy
- Head And Neck
-
-
Question 15
Incorrect
-
A patient had a left Colles' fracture, which you were able to repair. It was their second fragility fracture this year, and you'd like to provide them some tips on how to keep their bones healthy.
What percentage of the calcium in the body is kept in the bones? Only ONE response is acceptable.Your Answer:
Correct Answer: 99%
Explanation:Calcium is stored in bones for nearly all of the body’s calcium, but it is also found in some cells (most notably muscle cells) and the blood. The average adult diet comprises roughly 25 mmol of calcium per day, of which the body absorbs only about 5 mmol.
-
This question is part of the following fields:
- Endocrine Physiology
- Physiology
-
-
Question 16
Incorrect
-
Which of the following is most true of the sinoatrial node:
Your Answer:
Correct Answer: Frequency of depolarisation is increased by sympathetic stimulation.
Explanation:Cardiac myocyte contraction is not dependent on an external nerve supply but instead the heart generates its own rhythm, demonstrating inherent rhythmicity. The heartbeat is initiated by spontaneous depolarisation of the sinoatrial node (SAN), a region of specialised myocytes in the right atrium close to the coronary sinus, at a rate of 100-110 beats/min. This intrinsic rhythm is primarily influenced by autonomic nerves, with vagal influences being dominant over sympathetic influences at rest. This vagal tone reduces the resting heart rate down to 60-80 beats/min. To increase heart rate, the autonomic nervous system increases sympathetic outflow to the SAN, with concurrent inhibition of vagal tone. These changes mean the pacemaker potential more rapidly reaches the threshold for action potential generation.
-
This question is part of the following fields:
- Cardiovascular
- Physiology
-
-
Question 17
Incorrect
-
Which one of the listed cells are typically found in a granuloma?
Your Answer:
Correct Answer: Epithelioid cells
Explanation:Typically, a granuloma has Langhan’s cells (large multinucleated cells) surrounded by epithelioid cell aggregates, T lymphocytes and fibroblasts.
Antigen presenting monocytic cells are found in the skin are known as Langerhan’s cells.
-
This question is part of the following fields:
- General Pathology
- Pathology
-
-
Question 18
Incorrect
-
A 26-year-old female cuts her hand on a knife while preparing dinner but the bleeding stops within a few minutes.
Which one of the following cells will be among the first to be present at the wound site to be involved in haemostasis?Your Answer:
Correct Answer: Platelets
Explanation:Platelets are the first cells to be attracted to the wound site due to the release of the Von Willebrand factor from the damaged endothelium. Platelets, in turn, release cytokines such as platelet-derived growth factor, which will attract other inflammatory cells to the wound site.
-
This question is part of the following fields:
- General Pathology
- Pathology
-
-
Question 19
Incorrect
-
A 40-year-old female presents to the orthopaedic clinic complaining of pain and limited range of motion in the right elbow for the past two days. On examination, the right elbow is extremely tender with erythema and warmth of the overlying skin due to acute inflammation.
Which ONE of the following statements is true with regards to acute inflammation?Your Answer:
Correct Answer: Neutrophils are activated and adhere to the endothelium as a result of interaction with endothelial cell adhesion molecules
Explanation:Acute inflammation is defined as inflammation occurring within minutes to hours in response to an injury lasting for less than two weeks.
Acute inflammation
Rapid onset (minutes to hours)
Quick resolution (usually days)Chronic inflammation
May last weeks, months, or yearsThere are five cardinal signs of inflammation:
1) Pain
2) Redness
3) Warmth
4) Oedema
5) Loss of functionDuring acute inflammation, neutrophils are activated and attracted to the site of inflammation in response to various interleukins and cytokines. This process takes place via the following mechanism:
1) Margination
Neutrophils flow nearer the vessel wall rather than in the axial stream, which is referred to as margination
2) Rolling along the surface of vascular endothelium
3) Adhesion to the endothelium by interaction with adhesion molecules (ICAMS and VCAMS)
4) Diapedesis is the movement of neutrophils from the endothelial cells into the interstitial space by squeezing through the gaps between adjacent endothelial cellsBradykinin and histamine are both responsible for vasodilation which causes oedema and decreases intravascular osmotic pressure.
Neutrophils dominate early (<2 days)
– Many in the bloodstream
– Attach firmly to adhesion molecules
– Apoptosis after 24-48hrs
Monocytes/macrophages dominate late (>2 days)
– Live longer
– Replicate in tissues -
This question is part of the following fields:
- General Pathology
- Pathology
-
-
Question 20
Incorrect
-
The blood test reports of a 56-year-old female are sent for your review. She seems acutely sick and has had multiple infections over the past few months. Her complete blood count report shows neutropenia.
Which one of the following options is true with regards to neutropenia?Your Answer:
Correct Answer: It can be caused by both radiotherapy and chemotherapy
Explanation:A total neutrophil count of less than 2 x 109/L is defined as neutropenia. It can be caused by the following:
1. viral infections
2. SLE
3. RA
4. hypersplenism
5. chemo- and radiotherapy
6. vitamin B12 and folate deficiency
7. drug reactions -
This question is part of the following fields:
- Haematology
- Pathology
-
-
Question 21
Incorrect
-
Diabetic ketoacidosis is characterised by which of the following:
Your Answer:
Correct Answer: Hyperglycaemia, ketonaemia and acidosis
Explanation:DKA is characterised by the biochemical triad:
1. Hyperglycaemia (> 11 mmol/L)
2. Ketonaemia (> 3 mmol/L)
3. Acidosis (pH < 7.3 +/- HCO3 < 15 mmol/L) -
This question is part of the following fields:
- Endocrine
- Physiology
-
-
Question 22
Incorrect
-
The common bile duct drains into the duodenum in which of the following regions:
Your Answer:
Correct Answer: Second part of the duodenum
Explanation:As the common bile duct descends, it passes posterior to the first part of the duodenum before joining with the pancreatic duct from the pancreas, forming the hepatopancreatic ampulla (ampulla of Vater) at the major duodenal papilla, located in the second part of the duodenum. Surrounding the ampulla is the sphincter of Oddi, a collection of smooth muscle which can open to allow bile and pancreatic fluid to empty into the duodenum.
-
This question is part of the following fields:
- Abdomen
- Anatomy
-
-
Question 23
Incorrect
-
C5 - C9 deficiency increases susceptibility to infection with which of the following:
Your Answer:
Correct Answer: Neisseria spp.
Explanation:If the complement sequence is completed, an active phospholipase (the membrane attack complex, MAC) is produced, which punches holes in the cell membrane and causes cell lysis. Because the MAC appears to be the sole means to destroy the Neisseria family of bacteria, C5 – C9 deficiency increases susceptibility to Neisseria infections.
-
This question is part of the following fields:
- Immune Responses
- Pathology
-
-
Question 24
Incorrect
-
All of the following are indications for beta-blockers EXCEPT for:
Your Answer:
Correct Answer: Prinzmetal's angina
Explanation:Beta-blockers are contraindicated in Prinzmetal’s angina.Beta-blockers may be indicated in:HypertensionPheochromocytoma (only with an alpha-blocker)AnginaSecondary prevention after ACSArrhythmias including atrial fibrillationHeart failureThyrotoxicosisAnxietyProphylaxis of migraineEssential tremorGlaucoma
-
This question is part of the following fields:
- Cardiovascular
- Pharmacology
-
-
Question 25
Incorrect
-
All of the following cause bronchoconstriction, EXCEPT for:
Your Answer:
Correct Answer: Adrenaline
Explanation:Factors causing bronchoconstriction:
- Via muscarinic receptors
- Parasympathetic stimulation
- Stimulation of irritant receptors
- Inflammatory mediators e.g. histamine, prostaglandins, leukotrienes
- Beta-blockers
-
This question is part of the following fields:
- Physiology
- Respiratory
-
-
Question 26
Incorrect
-
You're evaluating a 37-year-old woman who is 12 weeks pregnant. She has experienced vaginal bleeding.
Which of the following anti-D statements is correct?Your Answer:
Correct Answer: Routine antenatal prophylaxis is recommended for RhD negative women at 28 and 34 weeks
Explanation:Anti-D is an IgG antibody that targets the antigen Rhesus D (RhD). Plasma from rhesus-negative donors who have been immunised against the anti-D-antigen is used to make anti-D immunoglobulin.
Only RhD negative women are given Anti-D Ig. Women who are RhD negative do not have the RhD antigen on their RBC. If a foetus has the RhD antigen (i.e. is RhD positive) and the mother is exposed to foetal blood, she may develop antibodies to RhD that pass through the placenta and attack foetal red cells (resulting in newborn haemolytic disease). Anti-D is given to bind and neutralise foetal red cells in the maternal circulation before an immune response is triggered. In the event of a sensitising event, 500 IU Anti-D Ig should be administered intramuscularly.
The following are examples of potentially sensitising events:
Birth
Haemorrhage during pregnancy
Miscarriage
Ectopic pregnancy
Death within the womb
Amniocentesis
Chorionic villus sampling
Trauma to the abdomenThe sooner anti-D is given in the event of a sensitising event, the better; however, it is most effective within 72 hours, and the BNF states that it is still likely to have some benefit if given outside of this time frame.
At 28 and 34 weeks, RhD negative women should receive routine antenatal prophylaxis. This is regardless of whether they have previously received Anti-D for a sensitising event during the same pregnancy.
Prophylactic anti-D is not necessary before 12 weeks gestation, as confirmed by scan, in uncomplicated miscarriage (where the uterus is not instrumented), or mild, painless vaginal bleeding, as the risk of foeto-maternal haemorrhage (FMH) is negligible. In cases of therapeutic termination of pregnancy, whether by surgical or medical means, 250 IU of prophylactic anti-D immunoglobulin should be given to confirmed RhD negative women who are not known to be RhD sensitised.
-
This question is part of the following fields:
- Immunological Products & Vaccines
- Pharmacology
-
-
Question 27
Incorrect
-
A 60-year-old patient with a history of hypertension and chronic kidney disease (CKD) walks into the clinic to discuss her most recent blood results indicating an accelerated progression of CKD.
Which of the following is the correct definition for accelerated progression of CKD?
Your Answer:
Correct Answer: A sustained decrease in GFR of 15 ml/minute/1.73 m 2 per year
Explanation:Chronic kidney disease (CKD) is a disorder in which kidney function gradually deteriorates over time. It’s fairly prevalent, and it typically remains unnoticed for years, with only advanced stages of the disease being recognized. There is evidence that medication can slow or stop the progression of CKD, as well as lessen or prevent consequences and the risk of cardiovascular disease (CVD).
CKD is defined as kidney damage (albuminuria) and/or impaired renal function (GFR 60 ml/minute per 1.73 m2) for three months or longer, regardless of clinical diagnosis.
A prolonged decline in GFR of 25% or more with a change in GFR category within 12 months, or a sustained drop in GFR of 15 ml/minute/1.73 m² per year, is considered accelerated CKD progression.
End-stage renal disease (ESRD) is defined as severe irreversible kidney impairment with a GFR of less than 15 ml/minute per 1.73 m² and a GFR of less than 15 ml/minute per 1.73 m². -
This question is part of the following fields:
- Physiology
- Renal Physiology
-
-
Question 28
Incorrect
-
You review a 46-year-old woman who has recently been prescribed antibiotics for a urinary tract infection. She suffers from COPD and is currently prescribed salbutamol and Seretide inhalers, and Phyllocontin continus. Since starting the antibiotics, she has been experiencing nausea, vomiting and abdominal pain.
Which of the following antibiotics is she MOST LIKELY to have been prescribed for her UTI? Select ONE answer only .Your Answer:
Correct Answer: Ciprofloxacin
Explanation:Phyllocontin continus contains aminophylline (a mixture of theophylline and ethylenediamine), a bronchodilator used in the management of COPD and asthma.
This patient is exhibiting symptoms of theophylline toxicity, which may have been triggered by the prescription of the antibiotic. Quinolone antibiotics, such as ciprofloxacin and levofloxacin, and macrolide antibiotics, such as erythromycin, increase the plasma concentration of theophyllines and can lead to toxicity.
The drugs that commonly affect the half-life and the plasma concentration of theophylline are summarised in the table below:
Drugs increasing plasma concentration of theophylline
Drugs decreasing plasma concentration of theophylline
Calcium channel blockers, e.g. Verapamil
Cimetidine
Fluconazole
Macrolides, e.g. erythromycin
Quinolones, e.g. ciprofloxacin
Methotrexate
Barbiturates
Carbamazepine
Phenobarbitol
Phenytoin (and fosphenytoin)
Rifampicin
St. John’s wort -
This question is part of the following fields:
- Pharmacology
- Respiratory Pharmacology
-
-
Question 29
Incorrect
-
All of the following statements are considered true regarding likelihood ratios, except:
Your Answer:
Correct Answer: A likelihood ratio less than 1 indicates that the result is associated with the presence of the disease
Explanation:The Likelihood Ratio (LR) is the likelihood that a given test result would be expected in a patient with the target disorder compared to the likelihood that that same result would be expected in a patient without the target disorder.
The LR is used to assess how good a diagnostic test is and to help in selecting an appropriate diagnostic tests or sequence of tests. They have advantages over sensitivity and specificity because they are less likely to change with the prevalence of the disorder, they can be calculated for several levels of the symptom/sign or test, they can be used to combine the results of multiple diagnostic test and they can be used to calculate post-test probability for a target disorder.
A LR greater than 1 produces a post-test probability which is higher than the pre-test probability. An LR less than 1 produces a post-test probability which is lower than the pre-test probability. When the pre-test probability lies between 30 and 70 per cent, test results with a very high LR (say, above 10) rule in disease. An LR below 1 produces a post-test probability les than the pre-test probability. A very low LR (say, below 0.1) virtually rules out the chance that the patient has the disease.
-
This question is part of the following fields:
- Evidence Based Medicine
-
-
Question 30
Incorrect
-
The most common source of healthcare-associated bacteraemia is:
Your Answer:
Correct Answer: Intravenous cannula
Explanation:Healthcare-associated bacteraemia is most commonly caused by intravenous access. Any intravenous device that is left in place for a long time increases the risk of infection. It allows bacteria like Staphylococcus aureus and Staphylococcus epidermidis to enter the body.
-
This question is part of the following fields:
- Microbiology
- Principles
-
00
Correct
00
Incorrect
00
:
00
:
00
Session Time
00
:
00
Average Question Time (
Mins)