Literature Eval Midterm Practice

A study provides results for the relative risk of myocardial infarction in patients receiving drug X: 95% CI = 0.75 (0.6-0.93)What is the relative risk for myocardial infarction?

A study provides results for the relative risk of myocardial infarction in patients receiving drug X: 95% CI = 0.75 (0.6-0.93)Drug X appears to reduce the risk of myocardial infarction somewhere in the range of: ___-___%

In the 4S study 4444 patients with high cholesterol and CHD were given either simvastatin or placebo.  After treatment for 5.4 years the following results were found:           Simvastatin group:      182 (8%) diedPlacebo group:            256 (12%) diedRR = 8% / 12% or 0.08 / 0.12 = 0.66From this we can conclude what about simvastatin and the risk of the chance of death:

• Since the result is < 1, then we can determine that simvastatin reduced the risk or the chance of death.

• Sine the result is < 1, then we can determine that simvastatin increased the risk or the chance of death.

• There is no significant difference between groups.

• We do not have enough information to answer.

In a randomized, controlled trial, Phil's Heart Supplement was compared to placebo for reducing the risk of myocardial infarction in patients with existing cardiovascular disease. One hundred (100) patients received Phil's Heart Supplements and 100 patients received placebo. After 2 years of treatment, 25 patients receiving Phil's Heart Supplement experienced a myocardial infarction. In the placebo group, 35 patients experienced a myocardial infarction. The difference was statistically significant (P < 0.05).Calculate the the relative risk of myocardial infarction and select the correct answer below.

• 0.71

• 1.4

• 0.69

• 0.61

When deciding how to use the findings of a clinical trial, which of the following should be considered?

• Validity of the evidence

• Clinical significance of the findings

• Risk versus benefit

• All the above

Practice guidelines in the United States use the same evidence-grading system, so an evidence rating of 2C can be universally applied across all guidelines.

• True

• False

What does the study NOT tell us? Select all the apply:

• The optimum dose of a drug (studies usually evaluate just one or two different doses)

• The optimum duration of therapy (usually just one duration is measured)

• Whether another drug might have been more effective in the particular population

• Whether certain combination therapies might be more effective

What are the ultimate goals of medicine?

• Improve health

• Improve quality of life

• Reduce cholesterol

• Improve quantity of life

• Save health care dollars

Evidence-based practice gives us the tools we need to know if the diagnostic tests and treatments we give actually contribute to achieving our ultimate goals.

• True

• False

Which of the following is not a low level question?

• Is lithium available as an oral solution?

• What are the storage requirements for dabigatran?

• Does the evidence support the use of montelukast for migraine prevention?

• What are the FDA-approved indications for gabapentin?

Setting filters on a search increases the number of results retrieved.

• True

• False

You are writing a review article on HMG-CoA reductase inhibitors (statins) and need to gather clinical trials evaluating their efficacy.  You are particularly interested in determining which, if any, of the statins have a mortality benefit in secondary prevention.  After conducting your search and setting your filters you read through the article abstracts and choose only those studies which assessed patient mortality as an outcome.  Thus, studies looking at mortality would meet your ___________ criteria.

• Inclusion

• Exclusion

• Evidence

• Cherry-picking

For most clinical questions regarding drug therapies, the most relevant research design is usually a:

• Randomized controlled trial

• Population Study

• Cohort study

• Case study

P value tells us the direction of the difference (better or worse, higher or lower, etc) and it tells us the strength or magnitude of the treatment effect.

• True

• False

Read the abstract below. Which of the following is true about the finding related to the primary outcome?  Coenzyme Q10 (CoQ10) deficiency has been proposed to be causal in 3-hydroxy-3-methyl-glutaryl coenzyme A reductase inhibitor (statin)-induced myopathies. However, the clinical benefit of supplementation is unproved. The purpose of the present study was to assess the effect of CoQ10 supplementation on myalgias presumed to be caused by statins. Patients currently receiving a statin who developed new-onset myalgias in ≥ 2 extremities within 60 days of initiation or a dosage increase were eligible. Patients continued statin therapy and were randomized using a matched design to either CoQ10 60 mg twice daily or matching placebo. Double-blind treatment continued for 3 months, and patients completed a 10-cm visual analog scale (VAS) and the Short-Form McGill Pain Questionnaire at baseline and at each monthly visit. The primary end point was the comparison of the VAS score at 1 month. A total of 76 patients were enrolled (40 in the CoQ10 arm and 36 in the placebo arm). The mean VAS score was 6 cm at baseline in both groups. At 1 month, no difference was seen in the mean VAS score between the 2 groups (3.9 cm in the CoQ10 group and 4 cm in the placebo group; p = 0.97). However, 5 patients in the CoQ10 group and 3 in the placebo group discontinued therapy during the first month because of myalgias. The baseline median score on the Sensory Pain Rating Index subscale was 10 in the CoQ10 group and 11.5 in the placebo group. At 1 month, these scores had decreased to 6.5 and 7.5, respectively, with no statistically significant difference (p = 0.34). In conclusion, CoQ10 did not produce a greater response than placebo in the treatment of presumed statin-induced myalgias.

• The difference is not statistically significant.

• There is a statistically significant difference.

• The difference is statistically significant, but not clinically significant.

• The difference is clinically significant, but not statistically significant.

Confidence intervals can tell us if results are statistically significant just like a P value.  They can also give us a much more descriptive picture of the true treatment effects.

• True

• False

In a randomized, controlled trial, Phil's Heart Supplement was compared to placebo for reducing the risk of myocardial infarction in patients with existing cardiovascular disease. One hundred (100) patients received Phil's Heart Supplements and 100 patients received placebo. After 2 years of treatment, 25 patients receiving Phil's Heart Supplement experienced a myocardial infarction. In the placebo group, 35 patients experienced a myocardial infarction. The difference was statistically significant (P < 0.05).What is the probability for the treatment group and the control group?

• Treatment = 25% Control = 35%

• Treatment = 75% Treatment = 75% Control = 65%

• Treatment = 35% Control = 25%

• Treatment = 71% Control = 40%

In a randomized, controlled trial, Phil's Heart Supplement was compared to placebo for reducing the risk of myocardial infarction in patients with existing cardiovascular disease. One hundred (100) patients received Phil's Heart Supplements and 100 patients received placebo. After 2 years of treatment, 25 patients receiving Phil's Heart Supplement experienced a myocardial infarction. In the placebo group, 35 patients experienced a myocardial infarction. The difference was statistically significant (P < 0.05). Calculate the the relative risk reduction or increase for myocardial infarction and select the correct answer below.

• 29% reduction

• 39% increase

• 71% reduction

• 39% reduction

Which of the following is included in "the big three" validity assessments?

• Was patient allocation adequately concealed?

• Were groups similar at baseline?

• Was a per-protocol or intention to treat analysis used?

• Were patients in each group treated similarly?

In a randomized, controlled trial, Phil's Heart Supplement was compared to placebo for reducing the risk of myocardial infarction in patients with existing cardiovascular disease. One hundred (100) patients received Phil's Heart Supplements and 100 patients received placebo. After 2 years of treatment, 25 patients receiving Phil's Heart Supplement experienced a myocardial infarction. In the placebo group, 35 patients experienced a myocardial infarction. The difference was statistically significant (P < 0.05). Calculate the the absolute difference for myocardial infarction and select the correct answer below.

• 10%

• 4%

• 0.71

• 29%

A P value of 0.05 means that there is a 5% probability that an observed difference is actually due to chance.  Similarly, there is a 95% probability that the observed difference represents a true difference that is not due to chance.

• True

• False

If the NNH is lower than the NNT then more people will experience harm than will experience benefit.

• True

• False

In a randomized, controlled trial, Phil's Heart Supplement was compared to placebo for reducing the risk of myocardial infarction in patients with existing cardiovascular disease. One hundred (100) patients received Phil's Heart Supplements and 100 patients received placebo. After 2 years of treatment, 25 patients receiving Phil's Heart Supplement experienced a myocardial infarction. In the placebo group, 35 patients experienced a myocardial infarction. The difference was statistically significant (P < 0.05). Calculate the the number needed to treat for myocardial infarction and select the correct answer below.

• 10

• 3

• 4

• 5

When there is a 1 to 1 ratio or a relative risk of "1" then there is a statistical difference

• True

• False

Which of the following is an appropriate method for random allocation?

• Flipping a coin

• Drawing straws

• Assignment based on eye color

• Drawing numbers from a hat

When a clinical trial provides a hazard ratio for the primary outcome, it is appropriate to also calculate the relative risk.

• True

• False

From top to bottom, which of the following is in the correct order with regard to the hierarchy of evidence?

• Systematic Reviews, Randomized Controlled Trials, Cohort Studies, Expert Opinion

• Cohort Studies, Systematic Reviews, Expert Opinion, Randomized Controlled Trials

• Randomized Controlled Trials, Cohort Studies, Systematic Reviews, Expert Opinion

• Expert Opinion, Randomized Controlled Trials, Systematic Reviews, Cohort Studies

A physician asks you about the interaction between proton pump inhibitors and clopidogrel. After researching the question, you make a recommendation to the physician to use rabeprazole 20mg daily in his patient. You base your recommendation on a handful of conflicting studies that use patient-oriented evidence. Most trials agree that rabeprazole is a safe and effective option, but they don't all agree. Based on the kind of evidence used, what SORT rating would you give this recommendation?

• B

• A

• C

A patient comes to your pharmacy and asks if the supplement SAM-e will help with her fibromyalgia symptoms.  You do some research and find that a few limited quality trials with patient oriented evidence found SAM-e to be beneficial for reducing fibromyalgia symptoms.  You recommend that the patient give SAM-e a try. True or False:  You should tell the patient that your recommendation has an evidence rating of B.

• True

• False

Evidence-based practice is defined by three components. Select the three components of evidence-based practice. 

• Systematic searching

• Clinical experience

• The best available evidence

• The most current evidence

• Randomized controlled trials

Which of the following are components of a well-built clinical question? Choose all that apply.

• Patient or Problem

• Patient Prognosis

• Intervention or treatment

• Outcomes

• Comparison

Systematic searching is important because it... (choose all that apply):

• Ensures that we look for the right kind of information to answer the question.

• Allows us to cherry pick evidence.

• Helps us know when to stop searching.

• Improves our efficiency in identifying evidence.

Which of the following outcomes would be considered patient-oriented evidence?

• HbA1c

• Kidney failure

• Hamilton D Rating Scale

• LDL levels

• Stroke

Review the following abstract and select the primary outcome below:  Coenzyme Q10 (CoQ10) deficiency has been proposed to be causal in 3-hydroxy-3-methyl-glutaryl coenzyme A reductase inhibitor (statin)-induced myopathies. However, the clinical benefit of supplementation is unproved. The purpose of the present study was to assess the effect of CoQ10 supplementation on myalgias presumed to be caused by statins. Patients currently receiving a statin who developed new-onset myalgias in ≥ 2 extremities within 60 days of initiation or a dosage increase were eligible. Patients continued statin therapy and were randomized using a matched design to either CoQ10 60 mg twice daily or matching placebo. Double-blind treatment continued for 3 months, and patients completed a 10-cm visual analog scale (VAS) and the Short-Form McGill Pain Questionnaire at baseline and at each monthly visit. The primary end point was the comparison of the VAS score at 1 month. A total of 76 patients were enrolled (40 in the CoQ10 arm and 36 in the placebo arm). The mean VAS score was 6 cm at baseline in both groups. At 1 month, no difference was seen in the mean VAS score between the 2 groups (3.9 cm in the CoQ10 group and 4 cm in the placebo group; p = 0.97). However, 5 patients in the CoQ10 group and 3 in the placebo group discontinued therapy during the first month because of myalgias. The baseline median score on the Sensory Pain Rating Index subscale was 10 in the CoQ10 group and 11.5 in the placebo group. At 1 month, these scores had decreased to 6.5 and 7.5, respectively, with no statistically significant difference (p = 0.34). In conclusion, CoQ10 did not produce a greater response than placebo in the treatment of presumed statin-induced myalgias.What was the primary outcome?

• VAS Score at 1 month

• McGill Pain Questionaire

• Sensory Pain Rating Index at baseline

• Statin-induced myalgia

In a study, 100 people were treated with vitamin D and 100 people received placebo control during the flu season. The researchers wanted to determine if vitamin D treated was associated with the risk of developing the flu. In the vitamin D group 22 patients developed the flu. In the placebo group, 29 patients developed the flu. The finding was statistically significant with a p < 0.05. Calculate the number needed to treat.

• 14

• 7%

• 4

• Cannot be calculated with the values given.

Which of the following are steps in the evidence-based approach to answering questions? Choose all that apply.

• Applying evidence to the patient case.

• Defining the question

• Critically appraising the evidence

• Searching PubMed

• Assessing study size and power

You are conducting a systematic search in PubMed to identify guidelines for the treatment of prostate cancer.  Which of the following filters would NOT be appropriate.

• Article type: Randomized Controlled Trial

• Language: English

• Species: Human

• Article Type: Practice Guideline

In a randomized, double-blind clinical trial, researchers were evaluating patients to determine the effect of Zombrex on mortality compared to placebo. At baseline, 45% of the patients in the treatment group were considered obese. In the placebo group, 25% were considered to be obese. Based on this information, this study is at risk for which threat to validity?

• Confounding

• Measurement bias

• Expectation bias

• Analysis bias

Which of the following is a threat to validity? Choose all that apply.

• Selection bias

• Crossover study design

• Financial conflict of interest

• Confounding

• Chance

Which of the following is an adequate method for concealing allocation?

• Third party random sequence assignment

• Random allocation

• Using a matching placebo treatment

• Flipping a coin

Most published studies don't actually have an impact on practice or don't necessitate a change in practice.

• True

• False

Review the following study abstract. Note that the primary outcome is knee pain severity as measured by the WOMAC scale. Which of the answers below correctly identifies the type of data for this outcome?  OBJECTIVE:To determine whether vitamin D supplementation reduces symptom and structural progression of knee OA.DESIGN, SETTING, AND PATIENTS:A 2-year randomized, placebo-controlled, double-blind, clinical trial involving 146 participants with symptomatic knee OA (mean age, 62.4 years [SD, 8.5]; 57 women [61%], 115 white race [79%]). Patients were enrolled at Tufts Medical Center in Boston between March 2006 and June 2009.INTERVENTION:Participants were randomized to receive either placebo or oral cholecalciferol, 2000 IU/d, with dose escalation to elevate serum levels to more than 36 ng/mL.MAIN OUTCOME MEASURES:Primary outcomes were knee pain severity (Western Ontario and McMaster Universities [WOMAC] pain scale, 0-20: 0, no pain; 20, extreme pain), and cartilage volume loss measured by magnetic resonance imaging. Secondary end points included physical function, knee function (WOMAC function scale, 0-68: 0, no difficulty; 68, extreme difficulty), cartilage thickness, bone marrow lesions, and radiographic joint space width.RESULTS:Eighty-five percent of the participants completed the study. Serum 25-hydroxyvitamin D levels increased by a mean 16.1 ng/mL (95% CI, 13.7 to 18.6) in the treatment group and by a mean 2.1 mg/mL (95% CI, 0.5 to 3.7) (P < .001) in the placebo group. Baseline knee pain was slightly worse in the treatment group (mean, 6.9; 95% CI, 6.0 to 7.7) than in the placebo group (mean, 5.8; 95% CI, 5.0 to 6.6) (P = .08). Baseline knee function was significantly worse in the treatment group (mean, 22.7; 95% CI, 19.8 to 25.6) than in the placebo group (mean, 18.5; 95% CI, 15.8 to 21.2) (P = .04). Knee pain decreased in both groups by a mean -2.31 (95% CI, -3.24 to -1.38) in the treatment group and -1.46 (95% CI, -2.33 to -0.60) in the placebo group, with no significant differences at any time. The percentage of cartilage volume decreased by the same extent in both groups (mean, -4.30; 95% CI, -5.48 to -3.12 vs mean, -4.25; 95% CI, -6.12 to -2.39) (P = .96). There were no differences in any of the secondary clinical end points.CONCLUSION AND RELEVANCE: Vitamin D supplementation for 2 years at a dose sufficient to elevate 25-hydroxyvitamin D plasma levels to higher than 36 ng/mL, when compared with placebo, did not reduce knee pain or cartilage volume loss in patients with symptomatic knee OA.

• Continuous

• Nominal

• Ordinal

• Categorical

Which of the following is NOT an experimental study design?

• Crossover Study

• Cohort Study

• Randomized Controlled Trial

In a study using a time-to-event analysis and measuring healing rates, the hazard ratio gives the odds that a patient receiving treatment will heal faster than a patient receiving placebo.  What additional information does the median ratio give?

• How much faster healing occurred with treatment compared to placebo

• The relative risk of healing faster

• The probability of healing faster with treatment compared to placebo

• The median ratio cannot be used with time-to-event analyses

Most of us feel more comfortable interpreting relative risk than odds ratio; however, in some study designs, a relative risk cannot be used. Which study design cannot use a relative risk calculation to estimate risk?

• Case control study

• Cohort study

• RTC

• Cross sectional study

Randomized control trials are the best source when searching for information on harm and/or etiology.

• True

• False

The preferred study type for a prognosis is:

• Cohort study

• Randomized controlled trial

• Meta analysis

• Public survey

For most clinical questions regarding diagnosis, the most relevant research design is a:

• Prospective, blinded comparison to gold standard

• Cohort Study

• Case Control

• Randomized controlled trial