USMLE STEP 1 Pharmacology
Number Needed to Harm
1/Attributable Risk =
1/[(Ppl w/ Intervention & Disease/Total Ppl w/ Intervention)-(Ppl w/o Intervention &
Disease/Total Ppll w/o Intervention)]
Factorial Study
Study design where different combination of treatments are given to different patient groups
Advantages include that researchers evaluate multiple independent variables at the same time
Internal Validity
The extent to which we can draw cause-and-effect inferences from a study
Affected by:
-Lack of Blinding
-Observer Bias
-Hawthorne Effect
Limited # of Participants
Parameter which limits Statistical Power
Regression Analysis
Study of 2+ independent variables which may be qualitative or quantitive and 1 dependent
variable while adjusting for others variables fo interest
Convenience Sampling
Survey method which uses a sample of people who are readily available to participate
I.e.
-Email surveys
-Standing in a public place + recruiting participants
,**Method is also known as "Grab sampling" or "Opportunity sampling"**
Cons
-High probability of Selection bias
-Sampling error (As these participants may not reflect the population at large)
Referral Sampling
Survey method wherein current participants recommend future participants
**Method is also known as "Chain sampling" or "Snowball sampling"**
Cons
-Generalizability of results
-Sampling error (As these participants may not reflect the population at large)
Stratification
Grouping/Subdividing a study population
Randominzation
A method to reduce Confounding Bias in a study
Ecological Study
Study in which the units of analysis are Populations or Groups of people rather than Individuals
Randomized Control Trials
Research technique where subjects receive either the new screening test or usual care
Intention to Treat
Analytic strategy which compares treatment groups in a randomized trial by including all
subjects as initially allocated after randomization. Observations are included regardless of what
happens during the study period (I.e. Non-adherence to treatment)
Hospice Care/Palliative Care
Provided to terminally ill pts w/ <6 months to live once aggressive/curative treatment is no
longer beneficial nor desired
Type of care which is based on the principle of providing compassionate care which focuses on
comfort + quality of care
, AUC
Parameter which quantifies the accuracy of screening diagnostic tests
-A highly accurate Test is highly Sensitive + highly Specific, thus the higher the Accuracy of a
Test, the closer to 1 the _______ level will be
Probability to conceive Affected Child if AR
1/4 X (Probability of Carrier Mother) x (Probability of Carrier Father)
Number Needed to Harm
1/(AEs for Intervention - AEs for Placebo)
Placebo Effect
The phenomenon in which the expectations of the participants in a study can influence their
behavior
I.e. Placebo is working and producing pain reduction when in reality, it does NOT contain the
new drug
Capitation
System of payment in which a Payor (Individual or Employer) pays a fixed predetermined fee per
patient to cover all required medical services
-This method of payment structure is adopted by Health Maintenance Organization and restricts
pts to a limited panel of providers
Global Payment
Arrangement in which an insurer pays a provider a single payment to cover all the expenses
associated w/ an incident of care
-This is most commonly done for Elective Surgeries
Point of Service Plans
Payment plan which requires patients to have a primary care provider and obtain referrals for
specialty consultations
-They differ from HMO plans in that they allow patients to see providers outside the network.
Case Series
Number Needed to Harm
1/Attributable Risk =
1/[(Ppl w/ Intervention & Disease/Total Ppl w/ Intervention)-(Ppl w/o Intervention &
Disease/Total Ppll w/o Intervention)]
Factorial Study
Study design where different combination of treatments are given to different patient groups
Advantages include that researchers evaluate multiple independent variables at the same time
Internal Validity
The extent to which we can draw cause-and-effect inferences from a study
Affected by:
-Lack of Blinding
-Observer Bias
-Hawthorne Effect
Limited # of Participants
Parameter which limits Statistical Power
Regression Analysis
Study of 2+ independent variables which may be qualitative or quantitive and 1 dependent
variable while adjusting for others variables fo interest
Convenience Sampling
Survey method which uses a sample of people who are readily available to participate
I.e.
-Email surveys
-Standing in a public place + recruiting participants
,**Method is also known as "Grab sampling" or "Opportunity sampling"**
Cons
-High probability of Selection bias
-Sampling error (As these participants may not reflect the population at large)
Referral Sampling
Survey method wherein current participants recommend future participants
**Method is also known as "Chain sampling" or "Snowball sampling"**
Cons
-Generalizability of results
-Sampling error (As these participants may not reflect the population at large)
Stratification
Grouping/Subdividing a study population
Randominzation
A method to reduce Confounding Bias in a study
Ecological Study
Study in which the units of analysis are Populations or Groups of people rather than Individuals
Randomized Control Trials
Research technique where subjects receive either the new screening test or usual care
Intention to Treat
Analytic strategy which compares treatment groups in a randomized trial by including all
subjects as initially allocated after randomization. Observations are included regardless of what
happens during the study period (I.e. Non-adherence to treatment)
Hospice Care/Palliative Care
Provided to terminally ill pts w/ <6 months to live once aggressive/curative treatment is no
longer beneficial nor desired
Type of care which is based on the principle of providing compassionate care which focuses on
comfort + quality of care
, AUC
Parameter which quantifies the accuracy of screening diagnostic tests
-A highly accurate Test is highly Sensitive + highly Specific, thus the higher the Accuracy of a
Test, the closer to 1 the _______ level will be
Probability to conceive Affected Child if AR
1/4 X (Probability of Carrier Mother) x (Probability of Carrier Father)
Number Needed to Harm
1/(AEs for Intervention - AEs for Placebo)
Placebo Effect
The phenomenon in which the expectations of the participants in a study can influence their
behavior
I.e. Placebo is working and producing pain reduction when in reality, it does NOT contain the
new drug
Capitation
System of payment in which a Payor (Individual or Employer) pays a fixed predetermined fee per
patient to cover all required medical services
-This method of payment structure is adopted by Health Maintenance Organization and restricts
pts to a limited panel of providers
Global Payment
Arrangement in which an insurer pays a provider a single payment to cover all the expenses
associated w/ an incident of care
-This is most commonly done for Elective Surgeries
Point of Service Plans
Payment plan which requires patients to have a primary care provider and obtain referrals for
specialty consultations
-They differ from HMO plans in that they allow patients to see providers outside the network.
Case Series
