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Biostatistics

It is a method of collecting, compilation, analysis, interpretation of data.

Data - These are the discrete observations of events which carry a little mean when considered alone. (Numerical countings.)

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Information - When data are reduced, summarized and adjusted to the variable factor such as (age, sex) are collectively known as information.

Intelligence - Integration of various data on the basis of social and political values.

(Data → Information → Intelligence)

Population - No. of individuals eligible for participating in any experiment are collectively known as population e.g. Hypertensive patients

Sample - Actual no. of individuals drawn from the population who are eligible for the experiment. Every individual is known as element.

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Collection :-

there are 2 ways for it :- i) Sources ii) Collection

Sources :-

1. Census
2. Records & documents

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3. Research paper & Publication

Method :-

1. Interview
2. Surveys
3. Questionnaire

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Compilation:-

i) Data summarisation ii) Data presentation

Quantitative Qualitative or Categorical

(Measurable) (Countable)

G.P Gender wise

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Height Religion wise

Wt., Hg. ABd grouping

Anaemia

Primary Secondary

Data collected by 1^st hand Data collected by already published, research, document.

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Continuous - (fractional Value) Hb

Discreate (Non-frac.) (No. of children in family)

Measurement :→

Scales of (Types of data).

Name-Nominal - Only name of categories involve. e.g-(religion, gender, colour)

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Order-Ordinal → Order of classification involve (1,2, 3rd division)

Interval → (Temp.^oC)

Ratio - Metric Scale. ( used for quantitative data). (Wt in gm.)

Interval - Interval keeps on changing.

No fixed zero. (0%)

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Ratio - fixed interval (Temp. in Kelvin)

fixed zero.

Special :-

i) Likert scale- Strongly when the responses are graded in agreed or disagreed.

(strongly disagree, Not agreed, No comment, Agreed, Strongly agreed)

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ii) VAS scale - Visual analogous score → 0-100 scale which measures intensity of pain used by surgeons & canaesthetics.

iii) Guttmann's Score - when importance of data or response is graded.

Smoking Lung CA

iv) Thurstone score- which measure attitude of the patient.

Compilation

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Data summarisation → Data presentation

Measurement-

Measures of Central tendency a) Range of dispersion

a) Mean (Arithmetic) b) Mean deviation

b) Median c) Standard deviation

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c) Mode

d) Geometric / harmonic mean

Data summarisation Presentation :-

Qualitative Quantitative

Bar Chart a) Histogram

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Pie Chart b) frequency polygone

Picto gram c) Live diagram

Scattered plot

Dott plot

Data summarisation

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Qualitative Quantitative.

frequency % Mode of dispersion

Mode of Central tendency Range

Mean Median Median deviation

Mode. SD.

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Data Presentation - Qualitative.

① Bar charts

x (Qualitative)

Magnitude x length of Bar

② Pie Charts -

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Magnitude x surface area

H - Haemorrhage

A - Anaemia

S - Sepsis

(Maternal Mortility) O - Obstructive labour

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T - Toxaemia

O - Others.

3) Pictogram - Pictorial representation of the numerical data.

also kla "Man in the street" graph.

Developed 500

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Developing 3500

undeveloped 10,000

Quantitative data -

1) Histogram (x-axis - Quantitative continous data are presented)

Simple Multiple Compound.

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One bar split

unto many...

Age pyramid of developing country

double simple Histogram.

2) frequency polygone

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3) Line diagram -

With respect to time distribution of any event or disease (Time trend)

4) Scattered plot

Dotted plot

④ cholesterol intake

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↑ SES

No. Alcohol/smoking ≠ PG Rank

It is va icorrelation stw dwo Variables. one may

↑ or ↓ or does not offert the other.

‘r’ = correlation coefficient.

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(-1 0 +1)

↑ SES ↓ IMR → +1

→ -0.8(√)

→-1

(IMR not only depend on SES).

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‘r²’ = coefficient of Determination.

(0-1)

(r² = (0.8)²- 0.64 = 64%)

In IMR 64% Variability due to SES.

Always represent in %

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+ve correlation Strong -ve No.

Measures of Central Tendency :→

a) Arithmetic mean = Σ Total no. of observation = 47.4.7

no. of observation 10

b) Median = 4+5 = 4.5

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c) Mode Most frequent Value = 2

d) Geometric Mean = √x₁x₂x₃…x_n

e) Harmonic Mean = n

Σ1/x reciprocal of mean including

reciprocal of observation

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‘14466237’ "Bimodal series" = 3x median - 2 mean

2 3 4 5 6.

Harmonic mean = 5.

½ + ⅓ + ¼ + ⅕ + ⅙

Mode of dispersion

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Range Mean deviation Standard deviation

1 2 3 4 5 6 7 8 9 1000

Most affected Value = Mean extreme Value.

Least = Mode. Sleewed Value.

Most prefessed Value = Median. Outlier Value.

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Most affected Value. Range (in mode of dispersion)

from, min → max.

Mean deviation = |x-x̄|

n (modulus)

Standard deviation = √(x-x̄)²

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η

15 ,25,25,30,33, 21, 25,18,25,40,18

Range Mean deviation S.Deviation

15 Range = (15-40)

18 a) Simplest measure (min → max.)

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18 difference bio two extremeties.

21

25

25 Mean deviation = Σ|x-x̄| = 300 = 25.

25 n Standard deviation 12

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25

25 |15-25| -10 (x-x̄)²

30

33 15 -10 100

40 18 -7 49 Root Mean Square

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18 -7 49 deviation I

21 -4 16 n>30 Σ(x-x̄)²

25 0 0 η

25 Ο 0

25 。 0 n <30 - Σ(x-x̄)²

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25 0 0 7-1

25 0 0 + 528

30 5 25 18

33 8 64 = √48

40 15 225 = 6.9

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538

Vital Statistics :-

1) Rate- 2) Ratio 3) Proportion

(N) D (N) D N

Multiplier v X ✓ (always 100%)

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10,000

10,000

time specific +/- ⊗ unstant.

Maternal Mortality Rate VI- CBR e.g- 1) case fatality rate

IMR CDR 2) proportional mortality rate

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NMR 3) Prevalence.

PNMR (postnatal) old + new cases

CBR

CDR

AGR (Annual growth Rate)

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SMR (Specific MR)

PAR (Incidence.

Maternal Mortality rate = total no. of maternal deaths

(complicat" + child birth + within 42 days)

Total no. of live birth. X1000

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Developed = 10,0000

Dendoping 1000

Infant Mortality death Total no. of children dt under tyrage x1000

Total no. of live birth

7 days - early neonate

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I mouth - Neonate

Im- Lys post neonate

I yt = Neonate

CBR. Total no. of dives birth x 1000

Med year population

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CDR = Total no. of death x1000

Mid yr pop

chinual growth rate. CBR-CDR

SMR = Total no. of deaths due to specific d/s x1000.

Mid year population

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Incidence = New cases

Prevalence- Incidence X duration

Point Period

(at unstant (time interval)

CFR- Total no. of death due to specific discase x100

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Total no. of case

PMR = Total no. of death due to specific disease x100.

Total no. of death

Ques Mid yr population = 5300

Potal death = 53

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Neonatal death = 10

deaths (Tetanus) = 6

Live birth 159

Infant death = 16

Total cases (TT)-300

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IMR = 16 x 1000

159

CDR- 53 X1000

5300

CBR = 159 x 1000

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5300

CFR = 6 x 100

300

PMR- 6 X 100

(tetanus) 53

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AGR- CBR-COR

159-53

5300 5300

SMR- 6 X 1000

5300

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VI = CBR

CDR

NMR- 10 x1000

159

PNMR = 6 x1000

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159

PMR (Juf - 16 x100

53

P

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