Biostats Flashcards
1
Q
Why is statistic important in medicine
A
Think scientifically about health problems
help in decision making from evidence
assess possible risk associated with medical decisions
identify decision that lack scientific and logical basis
2
Q
What are the two forms of statistics
A
Quantitative data collection
statistical methods
3
Q
What are the different methods of data collection
A
Routine data forms
surveys
experiments
4
Q
Methods of summarizing data
A
Tables
graphs
numerical statistic
5
Q
Methods for making inferences and estimations from data
A
Test of significant difference
test of association
estimation
6
Q
What are the three main uses of statistical methods
A
Collection of data
description of characteristics of a group or situation
analysis of data and drawing of conclusion
7
Q
What are the two types of statistics
A
Descriptive statistic
inferential statistic
8
Q
What is descriptive statistic
A
Description of characteristics of a product or process from information collected which summarize a group of scores to a single points
9
Q
What is inferential statistic
A
The drawing of conclusion on unknown process parameters based on information in a sample which uses probability
10
Q
What do you need to know in data collection
A
The type of research
the questionnaire design or interview guide design
sampling techniques
interviewing situations
11
Q
What are the different type of numeric format for summarizing data
A
Measures of central tendency like mean median mode geometric mean
measures of spread like standard deviation variance range percentile
12
Q
What are the different type of tabular format for summarizing data
A
Frequency distribution table cross tabulation
13
Q
What are the different type of graphical transformers for summarizing data
A
Histogram bar diagram pie diagram scatter diagram frequency polygon
14
Q
What are the different type of test of significance
A
The null hypothesis and P value t-test and t test table Z test and standard normal table the chi-squared statistics degrees of freedom confidence interval probability distribution
15
Q
The different type of estimation
A
Regression
correlation
16
Q
What is research
A
Systematic way of putting together information based on prior to main purpose to reach a conclusion which can be very favorable by your peers
17
Q
Different type of research
A
Primary data collection secondary data analysis formative exploratory research pilot studies of observational studies clinical trials programmatic research translational research
18
Q
What are the two types of primary research
A
Qualitative research
quantitative research
19
Q
What is qualitative research
A
Based on personal stories of people through questioning in specific areas of interest
20
Q
What’s techniques of data collection are involved in qualitative research
A
Interview guides direct observation checklist videography Notes Recording
21
Q
Qualitative research that I collective is usually nonnumeric or numeric
A
Nonnumeric
22
Q
What are the different types of qualitative research
A
Focused group discussion
individual direct interview
Key informant interview
special groups firsthand observation
23
Q
In qualitative research what type of support is used for analysis and reporting
A
Analysis of themes
computer software
24
Q
What is a focus group discussion
A
A group interview with a small number of demographically similar people who have common traits of experiences beliefs to share ideas
25
What are the steps in running a focus group discussion
```
Choose a topic
develop questions from topic
develop interview guide
choose notetaker And recorder of session
recruit participants five or 10 people
obtain consents
do self introduction
introduce discussion topic
get participants chance to speak with equal representation
End the meeting in time
Analyze data to provide feedback
```
26
What is quantitative research
Structured acquisition of data with participants that provide responses in pre-defined categories
No storytellin
27
Data collection tools in quantitative research
Forms
tally sheets
questionnaires
28
How are questionnaires administered in quantitative research
Through phone
self-administered
interviewer administered in face to face
mail
29
What are the mode of analysis and reporting of quantitative research
Numeric ,tabular ,graphical summaries
inferential statistics
computer software
30
does the interviewer matter in quantitative research
Yes can corrupt results
31
Most frequently used method of that’s a connection in quantitative analysis
person to person interview
32
When is a mail questionnaire advised
For sensitive to private issues with clear simple questions in the good postal system
33
Which one is stronger hypothesis driven research or exploratory research
Hypothesis driven research
34
What should be the characteristics of an hypothesis
Directional and related to underlying biological model or theoretical frameworks, justifiable
35
What is the 2 type of research question
Standard approach
| foreground question / formative research
36
How do you evaluate your research question
Use the picot analysis
37
What does the picot analysis mean
```
Patients population problem
intervention
comparison
outcome
time elements /type of study
```
38
What is an aim in research
A statement derived from research question , Broads
39
What are objectives in research
Statements derived from the end which are more specific contains action verbs and are listed as primary or secondary
40
What are the characteristics of objectives in research
```
They have to be SMART
Specific
measurable
attainable
realistic
time bound
```
41
What are the different type of data
Continuous Data
categorical data
binary data
42
What is continuous data
 uninterrupted range of values so data can only be collected in integers
Like bp, weight, age
43
What are examples categorical data
Race
ethnicity
country of birth
degree of agreements
44
What are example of the binary data
Yes or no
positive or negative
dead or alive
45
What are nominal data
Data can be labeled
46
What is ordinal data
Data that is put an order or on a rating scale
47
What is discrete data
Values that are distinct or separated and can only assume certain values with no intermediate values
48
It’s continues that are measurable or countable
Measurable
49
Is discrete data countable or measurable
Countable
50
What is a variable
A name, a symbol, a letter used to represent an item , category, in a data set
51
What are the different types of variables
Quantitative
| Qualitative
52
What is quantitative variable
Measured numerically
| Either discrete or continuous
53
What is qualitative variable
Description of category using characteristics of interest
| No numerical value
54
4 scales of measurement
Nominal
Ordinal
Interval
Ratio
55
Nominal scale of measurement
```
Categorical
Dichotomous
Qualitative
Data divided into different categories,
no order
```
56
Ordered scale of measurement
Inhérent or prédétermined order in categories but nominal
| Divided into categories that can be ranked
57
What is interval scale of measurement
Like ordinal scale but distances between two points are of known sizes
Arbitrary Zero point
58
Ratio scale of measurement
Like interval scale but with Zero point, meaningful & definite
59
Why are health indicators difficult to evaluate
Mostly not quantifiable
| More than one factor involved in results
60
Sources of dlatafor development of health indicators
```
Vital events register
Population & censures
Routine heath service & records
Sample surveys
Disease registers
```
61
. Characteristic of a good health indicator
Relevant, valid, specific, reliable l sensitive
62
What is data
Collection of information
63
Two main sources of data to health personnel
Routine data coming from health personnel ( routine hospital forms , registers )
Periodic ( research data like surveys and experiments ,clinical trials data )
64
3 methods of data collection
Routine forms
Sample surveys
Experiments
65
Examples of data sources
```
Vital events register
Population censuses
housing censuses
Routine health service records
Epidemiological surveillance data
Sample survey data
Disease registers
Experiment
```
66
Types of routine data collection forms
```
Laboratory form
OPD forms
Death register
Cancer register
Admission form
Diagnosis index card
```
67
examples of primary source of data
```
Registers
Telephone records
Interview guides
Clinical trials
Questionnaire
```
68
Secondary source of data example
Annual reports
| Publications
69
What are important factors to consider when collecting data
Good scientific procedure to determine sample
Sample size
Representativeness of sample \
Good instrument to serve purpose of data collection
70
What is the research protocol ( research steps when writing )
```
Title
Abstract
Introduction (background, problem rationale )
Literature review
Aims and objectives
Methodology
Plan for data analysis
Budget
References
```
71
2 types of epidemiological studies
Observational
| Experimental
72
What is observational study
Non experimental procedure in which nature determines exposure
73
2 types of observational studies
Descriptive
| Analytical
74
Example of descriptive study
Case report
Case series
Case studies
Cross sectional studies in general
75
Types of analytical study
Case control
Cohort
Retrospective cohort
Prospective cohort
76
Example of experimental studies
Clinical trials
77
What is close ended questionnaire
Possible answers are provided for choosing
78
What is Open ended questionnaire
Respondent provides their own answer
79
What are the difficulties of open ended questionnaire
Difficult to code and make comparisons
80
What is reliability
Extent to which measures are repeatable
| Consistency of measuring instrument
81
What is validity
Extent to which instrument does what it is intended to do
82
What is internal validity
How instrument measures content under investigation
83
What is external validity
Generalization to total population
84
What are the important points of the numberg code
```
Voluntary consent essential
Yield fruitful results
No unnecessary suffering
No predictable death / disability
Risk not greater than problem
Participants can stop anytime
Investigator stopped if harmful
```
85
Which declaration says “ interest of subject must prevail over interests of science and society “ and enforces privacy and informed consent
The declaration of Helsinki at world health assembly in 1964
86
3 basic principles of clinical research
Respect for persons with informed consent and privacy
Bénéficience out-weights maleficence
Justice
87
Code of conduct used by Europeans and Japanese in experiment
ICH guideline
88
Code of conduct used by USA in research
Code of federal regulations (CFR)
89
What is informed consent
Process by which fully informed participants in bio medical research make choices about participation in study
90
What information should a person have in informed consent
```
Not a one time activity
Research goals
Research procedure s
Why person targeted
Benefits and risks
Voluntary
Confidentiality ‘
Who to contact
```
91
8 elements of informed consent
```
Research and its procedure , methodology
Risks, discomfort
Benefits
Alternate treatments
Confidentiality
Voluntary participation
Compensation in case of injury
Contact in case of emergency
```
92
What is source document
First place where research data is written out
93
What are the essential documents
```
Informed consent form
Cv of investigators
Copies of protocol
Correspondance with sponsor
Local lab values
```
94
Who provide assent form in Ghana
Children between 10 to 18 years
95
Sponsor definition
Entity that takes responsibility to initiate , manage , finance the clinical trial but does not conduct it
96
What are the responsibilities of sponsors
```
Record keeping
Recruit qualified persons to conduct trial
Handling data
Verification of data
Data analyses
Preparation of reports
```
97
What is population
Total persons or items observed in given study
98
What is sampling
Some members of population are selected to observe purposes of drawing conclusions
99
What is a parameter
Characteristic of a population
100
Benefits of sampling
Save manpower , Time, finances
101
what is the law of statistical regularity
Sample from population possesses characteristics of larger group
102
What is the law of large numbers
The bigger the sample size the more accurate and steady the characteristic
103
Qualities of a good sample
```
Representative
Randomly selected to minimize bias
Large enough to increase precision
All characteristics of interest
Good research design
```
104
2 types of sampling
Probability sampling
| Non probability sampling
105
Types of probability sampling
```
Simple random sampling
Systematic sampling
Stratified sampling
Cluster sampling
Multistage sampling
```
106
Types of non probability sampling
```
Quota sampling
Snowball sampling
Purposive Sampling
Saturation sampling
Convenient sampling
```
107
Sample frame
Entire list of sampling members of population from which sample will be taken
108
Sampling unit
Individual members of sampling frame
109
What is simple random sampling
Each member of population has equal chance of being selected into sample
110
Is sampling frame required for simple random sampling
Yes
111
Three ways of obtaining simple random sampling
Balloting
Random digit table
Computer
112
What is systematic sampling
Sample selected at interval
113
Is sampling frame necessary in systematic sampling
Not necessary but can be used
114
Procedure of systematic sampling
Choose sample size
divide population to get k
Choose item between 1 and K at random
go down the frame and pick Kth item every time until you exhaust the frame
115
What is cluster sampling
Sampling unit is group instead of individual like households in villages
116
Is sampling frame necessary in cluster something
Yes
117
Procedure of cluster sampling
Villages selected at random
list of head created
sample selected from a list of head using simple random sampling
everybody related to head of household selected part of sample
118
What is stratified sampling
Separate heterogeneous population into homogeneous strata to allow evaluation of underrepresented groups
119
What is multistage sampling
multiple stage to sample
120
What is quota sampling
Population divided into groups which ideally represents what exist in the population
121
what is the limit of quota sampling
Selection bias
| can’t calculate sampling error
122
What is a snowball technique in sampling
Previously identified group members identify other members of the population until most of the population is named
123
In what cases can you use snowball technique
For drug users
illegal aliens
prostitutes
community opinion leaders
124
What is the situation technique in sampling
Interviewer select individuals into study while partially analyzing information collected and stuff when realize that no new information is added to the study
125
What cases are saturation technique used
In qualitative research
126
What is purposive sampling
Nonrandom method of sampling in which a group of people are sitting with particular characters are selected
127
What is the convenience sample technique
Simple drawings from population at hands
128
When is convenient sample useful
For pilots testing and quantitative work
129
What does minimal sample size depends on
Objective of study
level of confidence to estimate population parameter
level of acceptable error
consideration with available resources
130
What are some assumptions made to calculate sample size
```
Single statistic calculated
normal distribution of the statistic
sampling using simple random sample
only type one error
have 2 tail situation with null Hypothesis and alternative hypothesis different from zero
```
131
What data doyou need before calculating sample size
Objective of study is SMART
level of confidence
level of acceptable error
available resources
132
What is a type one error
Null hypothesis is rejected when it’s true
133
What is type ii error
Null hypothes is accepted when its false and alternate hypothesis is rather true
134
What is the formula of sample size using Cochran formula
n = (z^2 * p(1-p) ) / d^2
135
What is the formula of sample size using Slovinsformula
n= N/ 1+ Ne^2
