Presented at a PBL workshop held at the Faculty of Medicine King Fahad Medical City 29-30 March 2010 by Professor Omar Hasan Kasule Sr. MB ChB (MUK), MPH (Harvard), DrPH (Harvard) Department of Bioethics Faculty of Medicine King Fahad Medical City
1.0 DEFINITION / IDENTIFICATION OF THE PROBLEM
1.1 Assessing lectures vs assessing PBL: This workshop is an attempt at remedying a practical problem that we have been facing in the recent past: most of the curriculum is delivered by the student-centered PBL method but the examinations are set by lecturers basing in many cases on the lectures that they gave
1.2 Unassessed PBL items: skills & information: 2 main components of the student education are left out of the assessment: (a) the skills of problem solving and clinical reasoning (b) substantive information acquired during the PBL sessions.
2.0 OBJECTIVES OF THE WORKSHOP
2.1 Reasoning skills and knowledge: This workshop covers examination of students on skills and knowledge acquired during the PBL sessions. The structure of the examination mirrors the flow of the slow-release PBL. Students are asked to formulate hypotheses and answer questions according to the available information. They are then given additional information so that they can refine their hypotheses / answers.
2.2 Integrated examination: The structure allows for an integrated assessment of all disciplines covered in one case scenario: basic sciences, clinical care, community health, and ethics.
3.0 STRUCTURE / STAGES OF A PROBLEM-BASED EXAMINATION (PBQ / MINICASE)
3.1 Presenting scenario: A brief opening clinical scenario is presented to the students. They are then asked to list key information in the presentation. This tests their ability to distinguish between what is important / significant and what is redundant or irrelevant.
3.2 Symptoms and signs: The students are presented with presenting symptoms and signs. They are asked to suggest several alternative hypotheses to explain the symptoms and signs. They are expected to explain in scientific terms how each hypothesis leads to the symptoms / signs. They may also be asked what further information they would seek by history taking, clinical examination, laboratory, or radiological investigations to determine which hypothesis best explains the observed symptoms and signs or disprove the alternative hypotheses.
3.3 Physical examination / laboratory / radiological investigations: the students are presented with more information and are asked to identify their favored hypothesis. The emphasis varies according to the level of the students. For pre-clinical students emphasis is on laboratory data (hematology, biochemistry, physiology) or pathological data. For clinical students emphasis is on physical examination, radiology, and more sophisticated laboratory investigations.
3.4 Management: The students may be asked questions relating to surgical or medical management of the case.
3.4 Specific substantive questions: towards the end and at the various stages of the examination students are asked direct questions on knowledge of aspects related to the case. These questions may be from any of the basic sciences, clinical medicine, pharmacology, community health / community medicine, epidemiology / biostatistics, and bioethics. Basic science questions in particular should focus on the scientific basis for clinical reasoning underlying the choice of the hypothesis. Some questions may be purely soliciting knowledge only indirectly related to the case but within the LOs set for that exam
3.0 SOME PRACTICAL TIPS
3.1 Learning Objectives: A matrix of learning objectives / learning outcomes (LOs) covered during the semester must be made showing how each LO will be examined (MCQ, PBQ, SAQ, EMW, OSCE etc). It is best to spread out LOs among examination techniques but there is no problem if one LO is examined in more than one way as long as the expected responses are not exact duplicates.
3.2 Preparing the case scenarios: The best and quickest approach is to get an actual patient file and abstract the scenarios from it. In order to fit the LOs set out at the beginning, some 'doctoring' of the clinical and investigational data may be necessary. The preparation of the basic case scenarios should be done by a team of no more than 3 made up of basic scientist, a clinician, and a medical educationist. After the skeleton is prepared other disciplines that will also be involved in the assessment may add 'intercalations' in the scenario to be a basis for assessing their specific LOs such as community health, community medicine, epidemiology, biostatistics, ethics, etc.
3.3 Preparing the questions: Questions at each stage of the case scenario should be of 2 types: methodological and substantive. Methodological questions test student's reasoning and data interpretation to make hypotheses or reach specific conclusions. Substantive questions ask about specific knowledge items based on tutor notes and students' self-centered learning. Substantive questions should be written by discipline experts who also were tutors and have an idea of what students explored and have an insight into the depth that they reached. No question shall be submitted without a model answer. Finally as many faculty as possible should vet the questions either as individuals or in groups.
EXAMPLE #1: HIP FRACTURE
LEARNING OBJECTIVES BEING EXAMINED
LOs on descriptive and analytic statistics
LOB1. Define and illustrate descriptive statistics for numerical variables: averages: mean, median, mode and interrelations; measures of dispersion: mean deviation, variance, standard deviation, Z (standardized) score, quartiles, deciles, range=min-max)
.
LOB2: Define and illustrate descriptive statistics for categorical variables: tabulation, frequency, relative frequency, and cumulative frequency.
LOB3: Define and illustrate estimation of confidence interval, estimation for a population mean, and estimation for a population proportion
LOB4: Define and illustrate hypothesis testing, the process of hypothesis testing, and interpretation of p value,
LOB5: Describe and illustrate numerical / continuous statistical analysis: Independent and paired t tests as well as one-way ANOVA.
LOB6: Describe and illustrate non-parametric numerical data analysis: Mann-Whitney, Kruskal-Wallis, and the Wilcoxin-signed rank test.
LOB7: Describe and illustrate categorical / discrete statistical analysis: Pearson approximate chi square method, and Fisher’s exact method.
LOB8: Describe and illustrate proportions, rates, and ratios: crude, specific, and adjusted/standardized rates using the direct standardization method
LOBs on anatomy and physiology
LOB1: Describe the anatomy of the hip joint
LOB2: Discuss the interpretation of laboratory investigations
LOB3: Describe bone physiology / calcium metabolism in the elderly
LOBs on ethico-legal issues
LOB1: Discuss ethico-legal-fiqh issues of legal competence: ahliyyat
LOB2: Discuss ethico-legal issues relating to DNR orders
INSTRUCTIONS
This PBQ consists of 2 triggers. You will be given 1 hour to read and answer questions on trigger 1 and the answer books will be taken away. You will then be given another hour to read and answer trigger 2. Please review this PBQ for any errors or inconsistencies. Suggest improvements in the writing of the scenario and the questions asked.
1.0 TRIGGER #1
1.1 History:
Mrs Ilham a 62-year old grandmother slipped on the polished floor in the living room of her house and fell down on the floor. She lay on her back in severe pain crying for help. She was unable to get up or lift her right lower limb off the floor. When she attempted to do so, she experienced severe pain. She was taken by ambulance to the Emergency Room of the hospital for further examination and treatment. A brief history was taken at the hospital. She said she heard a loud snap as she fell and claimed that the fall caused her bones to break. This was the first time that this occurred to her. She admitted that her 65-year old sister had a similar fall and was admitted to hospital for several weeks. She denied history of any previous joint or bone disease. She has had her annual physical examination 2 weeks prior to the fall and the results were normal.
Questions on the history:
1. List significant items in the presentation and explain why you think they are significant
2. Comment on the statement 'the fall caused her bones to break'
1.2 Physical examination:
On physical examination at the emergency room, the patient appeared obese, apprehensive, and in severe pain. She was not anaemic and had no conjuctival jaundice. Vital signs were: blood pressure 130/85 mmHg, axillary temperature 37.1 degrees centigrade, radial pulse rate 88/minute & regular, and respiratory rate 18/minute.
The medical officer on duty noticed that the right lower limb was laterally rotated and seemed to shorter than the left lower limb. On palpation, the right hip region was tender and but no swelling was felt. Passive movement of the right thigh caused extreme pain.
The medical officer used a tape measure to determine the length of both lower limbs. He measured limb length in 2 ways: (a) from the iliac crest to the tip of the heel and (b) from the greater trochanter to the tip of the heel. Because the patient was in pain and moving he repeated the measurements on each limb several times and recorded as shown in table #1 and table #2.
Table #1: Measurement of lower limb length
Measurement Attempt | Limb length in centimetres (greater trochanter to heel) | |
Right Lower Limb | Left Lower Limb | |
1 | ||
2 | ||
3 | ||
4 | ||
5 | ||
Mean | ||
Standard Deviation | ||
Table #2: Measurement of lower limb length
Measurement Attempt | Limb length in centimetres (iliac crest to heel) | |
Right Lower Limb | Left Lower Limb | |
1 | ||
2 | ||
3 | ||
4 | ||
5 | ||
Mean | ||
Standard Deviation | ||
Arterial pulses were assessed at various corresponding points in both limbs. The rate and strength of the pulses were recorded as shown in the table #3
Table #3: Assessment of arterial pulses of the lower limbs
Site of assessment | Right Lower Limb | Left Lower Limb |
1. Femoral artery pulse mid inguinal ligament | ||
Beats per minute | ||
Strength | ||
2. Dorsalis Pedis artery on dorsum of foot | ||
Beats per minute | ||
Strength |
Sensation to the pin prick was assessed on both lower limbs and the results were presented in table #4.
Table #4: Assessment of surface sensation on both lower limbs
Site of assessment | Percentage of sensory loss | |
Right Lower Limb | Left Lower Limb | |
Thigh – anterior aspect | ||
Thigh – posterior aspect | ||
Leg – anterior aspect | ||
Leg- posterior aspect | ||
Foot – dorsal aspect | ||
Foot – ventral aspect | ||
Toes | ||
Toes | ||
Questions on the physical examination
1. Summarize the results in table #1 and table #2. What conclusion can you draw? What statistical test can you use to confirm your conclusion?
2. Summarize the results in table #3. How would you test the hypothesis that there is no significant difference between the right and left lower limbs?
3. What conclusions can you derive from table #4
2.0 TRIGGER 2
2.1 Laboratory measurements
The medical officer took a blood sample and asked for a complete analysis including serum electrolytes. The results are shown in table #6.
Table #6: results of blood tests
Result | 95% CI for normal population | ||
1. Full Blood Count | Hb | ||
Hct | |||
WBC | |||
Neutrophils | |||
Lymphocytes | |||
Monocytes | |||
Eosinophils | |||
Platelets | |||
2. BUSE | Sodium | ||
Potassium | |||
Chloride | |||
Phosphate | |||
Urea | |||
Creatinine | |||
Alkaline phosphatase |
2.2 Radiological report
A radiological examination of both the right and left hip regions was requested. An intracapsular fracture of the femoral neck was present on the right with the distal part of the femur rotated laterally and shifted proximally. The right side was normal morphologically but one of the nurses noted that the bones appeared ‘thin’.
2.3 Bone mineral density (BMD) measurements
Table #7 shows results of measurement of the patient’s bone mineral density using the technique of dual energy X-ray absorptiometry (DXA). Measurements were taken at the following sites: femoral neck, iliac crest, and the spine. BMD is measured in 2 ways: (a) as z-score = number of standard deviations away from the mean of the normal population aged 60-70 (b) t-score = number of standard deviations away from the mean of the normal population aged 20-30 years in that population.
Table #7: Bone mineral density data
Bone Mineral Density Measurement | ||
z-score | t-score | |
Left femoral neck | ||
Right femoral neck | ||
Left iliac crest | ||
Right iliac crest | ||
Lumbar spine | ||
Questions on trigger #2
1. Why did the grandmother fall down?
2. Explain anatomically why the right lower limb was shorter than the left lower limb
3. What conclusions can you derive from table #6
4. What conclusions can you derive from table #7
5. What is the most likely diagnosis in this patient
6. List at least 3 possible complications of this condition
7. Can you think of alternative diagnoses (differential diagnoses)
8. What is Trandelenberg’s test?
9. Describe the anatomy of the hip joint
3.0 TRIGGER #3 (ethico-legal issues)
A few hours after admission. Mrs Ilham was diagnosed as having had a pulmonary embolism. While struggling to breathe she told the nurses that she did not want to be resuscitated if her heart stopped. Her family told the doctors to disregard her views because she was too old to understand. The doctors asked the psychiatriast’s opinion regarding Mrs Ilham's mental competence before proceeding with their decision making.
Questions on trigger #3
QSN1: Describe the concept of a legal guardian, wali, for an incompetent patient (2 marks)
ANS1: Legal guardianship, wilayat, is legal authority given to a guardian, wali, to make and carry out decisions regarding the person, nafs, or wealth, maal of a legally incompetent person. The decisions of a guardian are binding.
QSN2: Outline the procedure for a DNR (do not resuscitate) order (3 marks)
ANS2: The decision should be discussed with a competent patient; the decision should be joint involving the patient and the clinical team; the decision should be reviewed on a regular basis because of the evolutionary nature of the clinical condition; the decision must be documented and witnessed; the decision must follow the existing guidelines of the hospital.
QSN3: Explain a disadvantage of an advance directive regarding CPR (3 marks)
ANS3: The evolving clinical circumstances may be different from those that the patient and the clinical team had in mind when deciding on the DNR. It is therefore a disadvantage to have the DNR because it may lead to an inappropriate procedure. In practice it is difficult to anticipate all the possible evolutions of the clinical scenario in the distant future.
QSN4: Explain the doctrine of clinical futility as the basis for a DNR order by a physician for an incompetent patient (2 marks)
ANS4: The physician can decide on DNR based on the clinical futility doctrine. However this doctrine is not easy to define exactly and can give rise to disputes if interpreted too broadly or too vaguely.
QSN5: Explain ethico-legal considerations in cases of a DNR order for an infant born with a congenital abnormality not compatible with life to adulthood (2 marks)
ANS5: The main issue here is preservation of life. If the infant has a chance of living even for a short time he/she should not be denied the chance of CPR.
EXAMPLE #2: CARDIAC FAILURE
LEARNING OBJECTIVES TO BE EXAMINED
LOBs on basic and Clinical Sciences
LOB1: Explain the physiology of dyspnea in cardiac failure
LOB2: Explain how cardiac dilatation leads to valvular incompetence.
LOB3: Explain the mechanism of edema formation in cases of cardiac failure
LOB4: Describe the hormonal control of fluid volume and blood pressure
LOB5: Describe the function of baroreceptors in blood pressure control
LOB6: Describe normal ECG tracings and the common abnormalities
LOB7: Discuss the pharmacology of drugs used commonly in heart failure
LOB8: Describe and explain the pharmacological actions of digoxin, diuretics, ACE inhibitors, beta blockers and warfarin.
Clinical LOBs
LOB1: Recognize normal heart sounds and murmurs
LOB2: Discuss elements of the diagnosis of heart failure
LOBs on community Health
LOB1
LOB2
LOBs on ethics
LOB1
LOB2
INSTRUCTIONS
The examination is partially done and there are some mistakes and inconsistencies. There are also many aspects that can be improved. The task is to turn this into a very good problem-based assessment question. Feel free to make changes to the scenario, to add / delete data and questions, and to amend any items that you feel can be made better
TRIGGER #1: Presentation in the emergency room
Mr Ali was brought to the emergency room by an ambulance on oxygen. He was sweating, short of breath, and pale. He said that her heart was racing. He had difficulty speaking. A brief history was taken with much difficulty. He was on treatment for hypertension for the past 10 years but was irregular in taking medication. He has never suffered from many heart failure problems. Mr Ali was well until 4 hours ago. He woke up because of feeling tightness in the chest and had difficulty breathing. He felt his heart beating widly strongly and loudly. He was taken by ambulance to the nearest hospital. The ambulance crew put him on oxygen.
Questions trigger #1
1. Summarize the clinical problems
2. List all possible explanations (hypotheses) to explain the clinical problems
3. What further information do you need to select the most likely explanation / hypothesis
4. Substantive question
TRIGGER #2: Examination in the emergency room
General examination revealed a well built man with temperature 37 degrees centigrade, heart rate 120 per minute regular but with low volume, respiratory rate 35/minute, blood pressure 120/60 mmHg, weight 80 kg, and height 171 cm. The hands were cold and clammy. The tongue and conjunctivae were bluish. The lower limb showed marked edema. A 3rd heart sound was heard with murmurs that were difficult to characterize. The liver was slightly enlarged. A few wheezes and crepitations were noted at the base of both lungs.
Questions on trigger #2
1. List the prominent clinical signs
2. List hypotheses that can explain the signs and provide the scientific explanation relating the hypothesis to the signs
3. List investigations that you would like to undertake at this stage to help determine the most likely explanation of the symptoms and signs. Give three scientific reasoning behind the choice of each investigation.
4. Substantive question(s)
TRIGGER #3: Clinical management
Mr Ali was admitted and was put on diuretics, digoxin, an anticoagulant, and an ACE inhibitor and several investigations were ordered. The ECG showed a ventricular rate of 170 bpm with Q waves V4-V6. The chest x-ray showed heart enlargement with extensive pulmonary edema. Serum electrolytes (with normal values) were Na+ = 132 mmol/L (135 - 145), K+ = 4.3 mmol/L (3.5 - 4.7), Urea = 8.3 mmol/L (2.5 - 8.0), and Creatinine = 140mcmol/L (60 – 110). The following were normal: Thyroid function tests (TSH) Troponin T, Full blood count, urinalysis, Glucose, and Cholesterol
Questions on clinical trigger #3
1. List abnormalities so far
2. How can the new information help you in refining your hypotheses
3. Discuss the pharmacological basis for the given drug treatment
Other substantive questions
1. Describe the anatomy of the cardiac electrical conducting system
2. Discuss the pharmacological actions of beta blockers on the heart and the vascular system
3. Describe the monitoring of patients on anticoagulant therapy
EXAMPLE #3: CARDIAC PROBLEM
INSTRUCTIONS:
This examination item has only a partially done scenario. Please complete it so that it is ready for student assessment. Feel free to modify the scenario. You are also expected to develop your own LOBs to be examined. Generate questions and model answers.
LEARNING OBJECTIVES TO BE EXAMINED
LOB1
LOB2
LOB3
LOB4
LOB5
Trigger #1: Presenting history
A 60 year old woman was seen in the emergency room complaining of weakness, fatigue, non-productive cough, weight gain and difficulty in breathing while climbing up stairs to his second floor apartment. She he had no symptoms at rest. She was used to sleeping on 2 pillows. She wakes up at night feeling suffocated. She often falls asleep while sitting watching T.V. She wakes up 3-4 times/night for urination
Questions on trigger #1
1.
2.
3.
Trigger #2: Physical examination
On examination, she had generalized body swelling, weight was 95Kg, height 165 cm. Vital signs revealed a blood pressure of 140/85 mmHg both arms, heart rate of 90 beats/min( regular) and respiratory rate of 28/min( labored). Cardiovascular examination revealed elevated jugular venous pressure. Her PMI (point of maximum impulse) shifted away to the sixth intercostal space outside the mid-clavicular line. Auscultation revealed abnormal heart sounds. Chest examination revealed bilateral rales and wheezing. Abdominal examination revealed an enlarged liver and the lower limbs showed bilateral pitting edema.
Questions on trigger #2
1.
2.
3.
Trigger #3: Investigations
Her serum electrolytes, sugar, urea, and creatinine results were within normal range. ECG showed Q waves in the anterior leads. Chest x-ray showed an enlarged heart and congestion of the lungs. She was put on multiple drugs: (digoxin, lisinopril daily, Aspirin daily and frusemide IV).
Questions on trigger #3
1.
2.
3.
EXAMPLE #4: RESPIRATORY PROBLEM
INSTRUCTIONS:
This examination item has only a partially done scenario. Please complete it so that it is ready for student assessment. Feel free to modify the scenario. You are also expected to develop your own LOBs to be examined. Generate questions and model answers.
LEARNING OBJECTIVES TO BE EXAMINED
LOB1
LOB2
LOB3
LOB4
LOB5
Trigger #1: Presenting history and examination
Mustafa is four-years-old boy brought by his mother to ER complaining of sore throat, fever, dry cough and difficult breathing. On examination the child was conscious, his respiratory rate was 30/min with inspiratory croup, O2 saturation was 95%, pulse 110/min and his accessory respiratory muscles were in action.
Questions on trigger #1
1.
2.
3.
Trigger #2: More history and examination
URT examination showed yellowish purulent spots covering hyperemic and diffusely enlarged tonsils. Similar spots were seen on adjacent areas of soft palate, and oropharyngeal and laryngeal mucosa. The pyogenic spots coalesced in some areas to form dirty necrotic membrane. The latter did not bleed on removal. Mustafa’s neck was swollen with enlarged upper cervical lymph nodes. Chest auscultation showed inspiratory wheezes. The patient had a history of recurrent tonsillitis with fever, especially in winter seasons. His mother claimed that she noticed similar spots -but white in color- distributed all over Mustafa’s mouth and throat after a period of antibiotic therapy, a year ago.
Questions on trigger #2
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2.
3.
Trigger #4: Further developments on the ward
The doctor decided to admit Mustafa to pediatric isolation room until he receives results of some lab investigations. He could not deny a possible need for tracheostomy. He took a throat swab for urgent Gram stain exam and bacterial culture/sensitivity. The following tests were also requested: CBC, ESR, ASOT, and C-RP. The infection control officer was notified about this case right away.
Questions on trigger #2
1.
2.
3.
