Dr Ajaz Ahmed Public health dentist

2. UTILIZATION OF BIOSTATISTICS IN
DENTISTRY
DR AJAZ AHMED
1ST YEAR PG
PHD

3. Contents
• Introduction
• History
• Branches of Biostatistics
• Basis of Biostatistics
• Applications of Biostatistics :
In Public Health Dentistry
In various fields of dentistry
In medicine
In Pharmacology

4. In modern medicine
Clinical medicine
In preventive medicine
In biotechnology
In genetics
In nutrition
• Applications and uses of Biostatistics as
figures
• Conclusion
• References

5. Statistics
• Statistics is a branch of mathematics dealing
with data collection, organization, analysis,
interpretation and presentation. ... In addition
to being the name of a field of study, the word
"statistics" also refers to numbers that are
used to describe data or relationships.

6. BIOSTATISTICS
• statistical processes and methods applied to
the collection, analysis, and interpretation of
biological data and especially data relating to
human biology, health, and medicine

7. • Biostatistics covers applications and
contributions not only from health, medicines
and, nutrition but also from fields such as
genetics, biology, epidemiology, and many
others

8. • It is mainly consists of various steps like
generation of hypothesis, collection of data,
and application of statistical analysis

9. • Any science needs precision for its
development.
• Precision is all the more important when it
comes to health sciences. For precision; facts,
observations or measurements have to be
expressed in figures

10. • Medicine is essentially an empirical science. It
depends on observations and not on theories
or theorems.
• As a part of clinical practice or research we
deal with many observations, which when
systematically arranged, are called Data.

11. • The process of converting data into
information requires a special approach called
statistics.
• ‘Statistic’ means a measured or counted fact
or piece of the information, stated as a figure
such as height of one person, birth weight of a
baby etc

12. It is important to understand that
numbers are used for the sake of
convenience and that the numerical
values allow us to perform the data
analysis.

13. HISTORY
• Sir Francis Galton is considered as the Father
of Biostatistics.
• He was the first to apply statistical methods to
the study of human differences and
inheritance of intelligence, and introduced the
use of Questionnaires and Surveys for
collecting data on human communities, which
he needed for genealogical and biographical
works and for his anthropometric studies.

14. Origin and development of statistics in
medical research
• In 1929,a huge paper on application of
statistics was published in physiology journal
by Dunn.
• In 1937, 15 articles on statistical methods by
Austin Bradford Hill, were published in book
form.

15. • In 1948, a RCT of streptomycin for pulmonary
tb., was published in which Bradford Hill has a
key influence.
• Then the growth of statistics in Medicine from
1952 was a 8-fold increase by 1982.

16. BRANCHES OF BIOSTATISTICS
Descriptive
deals with the presentation and collection of
data. This is usually the first part of a statistical
analysis. It is usually not as simple as it
sounds, and the statistician needs to be aware
of designing experiments, choosing the right
focus group and avoid biases that are so easy
to creep into the experiment.

17. Inferential Biostatistics
As the name suggests, involves drawing the
right conclusions from the statistical analysis
that has been performed using descriptive
statistics. In the end, it is the inferences that
make studies important and this aspect is
dealt with in inferential statistics.

18. • Most predictions of the future
and generalizations about a population by
studying a smaller sample come under the
purview of inferential statistics

19. Basis of Biostatistics
Sources of medical Uncertainties
• Intrinsic due to biological, environmental and
sampling factors.
• Natural variation among methods, observers
and instruments etc.
• Errors in measurement or assessment or
errors in knowledge.
• Incomplete knowledge.

20. Intrinsic variation as a source of
medical uncertainties
• Biological due to age, gender, heredity,
height, weight etc. Also due to variation in
anatomical, physiological and biomechanical
parameters.
• Environment due to nutrition, smoking,
pollution, facilities of water and sanitation,
road traffic, legislation, stress and strain etc.

21. • Sampling fluctuations because the entire
world cannot be studied and at least future
cases can never be included.
• Chance variation due to unknown or complex
to comprehend factors.

22. • Biostatistics is the term used when tools of
statistics are applied to the data that is
derived from biological sciences such as
medicine.
• Any science demands precision for its
development, and so does medical science.
For precision, facts, observations, or
measurements have to be expressed in
figures.

23. • Everything in medicine be it research,
diagnosis or treatment, depends on counting
or measurement.
• High or low blood pressure has no meaning,
unless it is expressed in figures.
• Thus medical statistics or biostatistics can be
called Quantitative medicine

24. • In nature, blood pressure, pulse rate, action of
a drug or any other measurement or counting
varies not only from person to person but also
from group to group.
• The extent of this variability in an attribute or
a character, whether it is by chance i.e.
biological or normal, is learnt by studying
statistics as a science.

25. • Variation more than natural limits may be
pathological, i.e., abnormal due to the play of
certain external factors. Hence biostatistics
may also be called a science of variation.

26. • The data after collection, lying in a haphazard
mass are of no use, unless they are properly
sorted, presented, compared, analyzed and
interpreted.
• For such a study of figures, one has to apply
certain mathematical techniques called
statistical methods.

27. • For such a study of figures, one has to apply
certain mathematical techniques called
statistical methods.

28. • It is the science which deals with development
and application of the most appropriate
methods for the:
 Collection of data.
 Presentation of the collected data.
 Analysis and interpretation of the results.
 Making decisions on the basis of such analysis.

29. • Statistics arising out of biological sciences,
particularly from the fields of Medicine and
Public health.
• The methods used in dealing with statistics in
the fields of medicine, biology and public
health for planning, conducting and analyzing
data which arise in investigations of these
branches.

30. • The following are some examples in which
biostatistics is applied to answering questions
raised by researchers in the field of health
sciences

31. ROLE OF BIOSTATISTICS
• 1) Planning or designing the study
• 2) Data collection where we gather, record,
and check the needed information
• 3) Data analysis
• 4) Presentation of results and
• 5) Interpretation of the results in context
• Not too surprisingly, biostatistics can play a
role in each of these steps.

32. • Identify and develop treatments for disease and
estimate their effects.
• Identify risk factors for diseases.
• Design, monitor, analyze, interpret, and report results
of clinical studies.
• Develop statistical methodologies to address questions
arising from medical/public health data.
• Locate , define & measure extent of disease Ultimate
objective
• improve the health of individual & community

33. APPLICATION OF BIOSTATISTICS

34. APPLICATIONS OF BIOSTATISTICS

35. IN PUBLICHEALTHDENTISTRY
• To find the statistical difference between
means of two groups.
Ex: Mean plaque scores of two groups.

36. • To assess the state of oral health in the
community and to determine the availability
and utilization of dental care facilities.
• To indicate the basic factors underlying the
state of oral health by diagnosing the
community and find solutions to such
problems

37. • . To determine success or failure of specific
oral health care programs or to evaluate the
program action.
• To promote oral health legislation and in
creating administrative standards for oral
health care delivery.

38. • To compare health status of different group of
population.
• To study association and relationship between
variables eg
Sugar intake dental caries
Fluorosis and conc. Of Fluoride in water
Compare action of two different drugs

39. • Smoking and Oral cancer (CHI SQ TEST)
• Comparing efficacy of two different pates
(ANOVA )
• To test level of standard of health rising
and falling

40. • Experimental testing efficacy of tooth
paste (STRATIFIED RANDOM SAMPLING)
• Prevalence of malocclusion in urban and
rural population
• School oral health survey ( MULTIPHASE
SAMPLING

41. IN SYSTEMIC EVIDENCE BASED DENTISTRY
• Systemic collection and incorporation of
research evidence into clinical practice
• Hierarchy of evidence ... Systemic review and
metaanlysis
• Collect existing information

42. • Generate a data to establish scientific finding
• Meta analysis of result from several
independent studies
• Identify common effect of set of studies and
to improve precision of estimate

43. IN PERIODONTICS
• In dental sciences, gingival recession
represents a significant concern for patients
and a therapeutic problem for clinicians.
• A clinical study was conducted to evaluate
and compare the effects of a guided tissue
graft in the treatment of gingival recession
defects.

44. IN ORTHODONTICS
• Dental researches conducted a study to
evaluate relevant variables that may assist in
indentifying orthodontic patients with signs
and symptoms associated with sleep apnea
and to estimate the proportion of potential
sleep apnea patients whose ages range from 8
to 15 years.

45. IN ORAL MEDICINE
• candidiasis is a common infection among the immuno
compromised patients. The most causative agent is Candida
albicans , which is a fungus that produces chlamydospores .
• C.albicians can be harbored in the bristles of a toothbrush
and possibly re infect the patient during treatment .
• A study was conducted to determine the effectiveness of
the three most popular mouthrinses against C.albicians that
is harboured in the bristles of the toothbrush.

46. • Most of the scientific investigations typically
go through several steps.
• 1.Formulation of the research problem
• 2.Identification of key variables
• 3.Statistical design of an experiment
• 4.Collection of data
• 5.Stastistical analysis of the data
• 6.Interpretation of the analytical results

47. AS A SCIENCE
• TO COMPARE EFFICACY OF DRUGS IN
EPIDEMIOLOGICAL SURVEYS
• IN CLINICAL DENTISTRY FOR CONDUCTING AND
PLANNING OF CLINICAL TRIALS
• FOR EVALUATION OF MERITS AND DEMERITS OF
CLINICAL TRIALS
• IN PREVENTIVE DENTISTRY TO EVALUATE HEALTH
PROGRAMMES

48. • To find the difference between means and
proportions of normal at two places or in
different periods.
• Eg : The mean height of boys in Gujarat is less
than the mean height in Punjab. whether this
difference is due to chance or a natural
variation or because of some other factors
such as better nutrition playing a part, has to
be decided.

49. To find the correlation between two variables
X and Y such as height and weight.
whether weight increases or decreases
proportionately with height and if so by how
much, has to be found.

50. IN PHARMACOLOGY
• To find the action of drug
• a drug is given to animals or humans to see
whether the changes produced are due to the
drug or by chance.
• To compare the action of two different drugs
or two successive dosages of the same drug.
• To find the relative potency of a new drug
with respect to a standard drug.

51. IN MEDICINE
• To compare the efficacy of a particular drug, operation or line of
treatment – for this, the percentage cured, relieved or died in the
experiment and control groups, is compared and difference due to
chance or otherwise is found by applying statistical techniques.
• To find an association between two attributes such as oral cancer
and smoking or filariasis and social class –an appropriate test is
applied for this purpose.
• To identify signs and symptoms of a disease or syndrome.
• Cough in typhoid is found by chance and fever is found in almost
every case.
• The proportional incidence of one symptom or another indicates
whether it is a characteristic feature of the disease or not.

52. • To test usefulness of sera and vaccines in the
field – percentage of attacks or deaths among
the vaccinated subjects is compared with that
among the unvaccinated ones to find whether
the difference observed is statistically
significant.

53. • In epidemiological studies – the role of
causative factors is statistically tested.
• Deficiency of iodine as an important cause of
goiter in a community is confirmed only after
comparing the incidence of goiter cases
before and after giving iodized salt.

54. Modern medicine
• For decades, Biostatistics has played an integral
role in modern medicine in everything from
analyzing data to determining if a treatment will
work to developing clinical trials.
• The University of North Carolina's Gillings School
of Global Public Health defines biostatistics as
"the science of obtaining, analyzing and
interpreting data in order to understand and
improve human health.”

55. • Most people have heard the statistic that
Heart disease is the leading cause of death in
America today*.
• But how do we know this fact to be true?
Where did that information come from?

56. • Back in 1948, when a lot wasn't known about
the factors leading to heart disease and
stroke, a health research study -- known as the
Framingham Heart Study -- was done on 5,209
people living in the town of Framingham,
Mass.
• These participants hadn't developed any
known symptoms of cardiovascular disease
and hadn't had a stroke or heart attack.

57. • They agreed to be followed over a period of time
to help researchers learn what factors lead to
both conditions.
• The study was landmark in several ways. It
showed that there was no one cause for getting a
heart attack, and combining information about
several risk factors could estimate the risk of
someone getting the disease

58. • Thanks to the Framingham Study, (which is
still going on today), we now know the major
risk factors that lead to cardiovascular disease.
To reach these conclusions, researchers simply
followed the numbers -- the Biostatistics
numbers to be exact.

59. CLINICAL MEDICINE
Documentation of medical history of diseases.
Planning and conduct of clinical studies.
Evaluating the merits of different procedures.
In providing methods for definition of ‘normal’
and ‘abnormal’.

60. PREVENTIVE MEDICINE
• To provide the magnitude of any health
problem in the community.
• To find out the basic factors underlying the ill-
health.
• To evaluate the health programs which was
introduced in the community(success/failure).
• To introduce and promote health legislation.

61. Role of Biostatistics in Health
Planning and Evaluation
• Statistics arising out of biological sciences,
particularly from the fields of Medicine and
Public health.
• The methods used in dealing with statistics in
the fields of medicine, biology and public
health for planning, conducting and analyzing
data which arise in investigations of these
branches.

62. • In carrying out a valid and reliable health
situation analysis, including in proper
summarization and interpretation of data.
• In proper evaluation of the achievements and
failures of a health programs.

63. Biotechnology
• Biotechnology can focus on a whole range of
topics, from genetic modification of plants and
animals to gene therapy, medicine and drug
manufacturing, reproductive therapy, and even
energy production.
• In all cases, research is carried out by developing
something and testing whether or not it has the
desired performance.
• Determining performance requires statistical
analysis of results.

64. IN COMMUNITY MEDICINE AND
PUBLIC HEALTH
• To evaluate the efficacy of sera and vaccines in
the field.
• In epidemiological studies-the role of
causative factors is statistically tested.
• To test whether the difference between two
populations is real or a chance occurrence.

65. • To study the correlation between attributes in
the same population.
• To measure the morbidity and mortality.
• To evaluate achievements of public health
programs.
• To fix priorities in public health programs.
• To help promote health legislation and create
administrative standards for oral health.

66. • It helps in compilation of data, drawing
conclusions and making recommendations.
• For students of medicine/dentistry
• By learning the methods in biostatistics a student
learns to critically evaluate articles published in
medical and dental journals or papers read in
medical and dental conferences.
• To understand the basic methods of observation
in clinical practice and research.

67. In GENETICS
• Statistics and Human Genetics are twin subjects,
having grown with the century together, and
there are many connections between the two.
• Some fundamental aspects in particular the
concept of Analysis of Variance, first arose in
Human Genetics, while statistical and
probabilistic methods are now central to many
aspects of analysis of questions is human
genetics.

68. • The most common areas where one can find
an extensive applications of statistical
methods in human genetics is * Human
Genome Project * Linkage Analysis *
Sequencing

69. • IN Environmental science Environmental
statistics covers a number of types of study:
Baseline studies to document the present state
of an environment to provide background in
case of unknown changes in the future.

70. • Targeted studies to describe the likely impact
of changes being planned or of accidental
occurrences.
• Regular monitoring to attempt to detect
changes in the environment.

71. In NUTRITION
• Over the past 2 decades, there have been
revolutionary developments in life science
technologies characterized by high
throughput, high efficiency, and rapid
computation.
• Nutritionists now have the advanced
methodologies for the analysis of DNA, RNA,
protein, low- molecular-weight metabolites,
as well as access to bioinformatics databases.

72. • Biostatistics, which can be defined as the
process of making scientific inferences from
data that contain variability, has historically
played an integral role in advancing nutritional
sciences.
• Currently, in the era of systems biology
statistics has become an increasingly
important tool to quantitatively analyze
information about biological macromolecules

73. • Appropriate statistical analyses are expected
to make an important contribution to solving
major nutrition-associated problems in
humans and animals (including obesity,
diabetes, cardiovascular disease, cancer,
ageing, and intrauterine growth retardation).

74. Application and Uses of Biostatistics
As Figures
• Health and vital statistics are essential tools in
demography, public health, medical practice
and community services.
• Recording of vital events in birth and death
registers and diseases in hospitals is like book
keeping of the community, describing the
incidence or prevalence of diseases, defects or
deaths in a defined population.

75. • Such events properly recorded form the eyes
and ears of a public health or medical
administrator.
• What are the leading causes of death?
• What are the important cause of sickness?
• Whether a particular disease is rising or falling
in severity and prevalence? etc.

76. Conclusion
• Bio-statistical techniques can assure that the
results found in such a study are not merely
because of chance.
• In every case of our life, Statistics plays a
major role for better gaining and accurate
results.
• A well-designed and properly conducted
study is a basic prerequisite to arrive at valid
conclusions.

77. REFERENCES
 “Biostatistics.” Merriam-Webster.com Dictionary, Merriam-
Webster, https://www.merriam-
webster.com/dictionary/biostatistics. Accessed 19 May.
2020
 Siddharth Kalla (Aug 6, 2011). Branches of Statistics.
Retrieved May 11, 2020 from
Explorable.com: https://explorable.com/branches-of-
statistics
 Methods in Biostatistics sixth edition : BK
Mahajan
 Biostatistics – A foundation for Analysis in
the Health Sciences: Wayne W. Daniel,
Seventh Edition, Wiley Students Analysis.

78. Fundamentals of Biostatistics : Sanjeev BS
Johns Hopkins – Introduction to Biostatistics
Rao KV. Biostatistics: A manual of statistical
methods for use in health, nutrition and
anthropology. 2nd ed. New Delhi: Jaypee
Brothers Medical Publisher (P) ltd; 2007.
A First Course in Statistics with Application:
A.K. P. C Swain, Kalyani Publishers

79. THANKYOU